-Britain’s royal palaces.

Historic... -This, a twin-towered Italianate vision by the sea.

-...extravagant... -It just shouts power and richness.

-...and jam-packed with secrets.

-Their floating palace was the only palace that didn’t leak.

-In this series, we gain privileged access inside palace walls... -I’m heading for one of the most unexpectedly spectacular and costly parts of the palace -- the roof.

-...and uncover the hidden treasures within.

-It wasn’t until the fire that these beautiful paintings were rediscovered.

-We unearth the palaces' dark, secret histories... -Kew Palace had been a secret place of torture.

-...and we reveal the truth behind their most dramatic moments.

-Charles and Camilla probably just had their head in their hands and thought, "What else could go wrong?"

-This was the closest that Hitler got to actually killing the British royal family.

-I sat bolt upright in bed, saying, "What fire at Buckingham Palace?"

-Heavy is the head that wears the crown.

-This is the all new "Secrets of the Royal Palaces."

This time, what happened at Windsor when Kate took her princess test... -If the monarch doesn’t like the girlfriend, the marriage is not gonna happen.

-...the priceless palace treasures designed to hide a secret... -The only requirement was that they were unique and that each one contained a surprise.

-...how giving birth in a palace won’t protect your modesty... -And it has to be said that the most well sought-after spot to stand in was at the business end.

-...and why one overlooked palace might just be the most important of all.

-Buckingham Palace may be where the monarch lives, but St James’s is where the crown resides.

♪♪ -But first, the secret story of the palace that made the Queen cry.

-It was very shocking for the British public to see the Queen being emotional.

It’s something we’d never seen before.

-The tears almost flowed.

Her lips almost trembled.

You could see she was trying to fight back her huge sadness, and the Duke beside her just looked very serious, very grave, very upset.

-And the cause of her sadness -- bidding farewell to her most unique royal residence, her floating palace.

-I remember very clearly the day of the decommissioning of Britannia.

It was freezing cold.

We were down at Portsmouth, and for 13 hours, I stood on that dockside and froze.

But my problems were nothing compared to the Queen’s.

-There you had all the royal family on the quayside, all the ship’s crew lined up.

The one person who wasn’t there was the Queen mother, who just decided it was too painful, so she just stayed away.

-This had been more than just a yacht.

Britannia was the only home the Queen ever chose for herself.

-Many monarchs leave behind a legacy in bricks and mortar, in the form of a palace or royal residence that they have designed and built.

That’s not the case with Queen Elizabeth.

The nearest she’s got was the royal yacht.

-The announcement that there was going to be a new royal yacht came just a few years, actually, into the marriage of Elizabeth and Philip.

It was 1951, and probably to their great joy, they were told that a new royal yacht was going to be commissioned to replace the Victoria and Albert III, which was about 50 years old by that time.

-From the very start, the Queen and Prince Philip took a very keen interest.

Prince Philip was particularly interested in the more nautical side of things, but the Queen took a very keen interest in all the designs, particularly the interiors.

-By April 1953, the Queen’s personally designed ship was ready to go.

-The launch of Britannia was big news.

This yacht was going to be emblematic of this new age, this new reign.

It didn’t have a name to start with.

It was just given a code number.

-There’s not a lot you can probably keep secret about the design of a new ship up at Clydebank.

It was fairly public knowledge, I suppose, what the ship was going to look like, but one thing they could keep secret was what was she going to be called?

-I name this ship Britannia.

I wish success in all who sail in her.

[ Cheers and applause ] -When the Queen got on board Britannia, she was home and she was private and she was relaxed.

-And to help the Queen stay relaxed, she had the most discreet of crews.

-The sailors wear soft-soled shoes so they don’t make any noise as they walk up and down decks.

The sailors communicate with hand signals rather than shouting at each other so as not to disturb the royals.

-The crew on board Britannia were very trusted by the royals, and rightly so.

It was said that it was the only palace that didn’t leak.

-In this atmosphere of rare privacy, Britannia developed a racy reputation as the royal Love Boat.

-The first royal honeymoon in the yacht was Princess Margaret in 1960, when she married the Earl of Snowdon.

-The royal yacht, at the moment a very magnificent honeymoon cruise yacht, brought Princess Margaret and her husband on a brief visit to Trinidad.

-The only time that double beds would be brought on as if there was a honeymoon.

-Princess Margaret and Lord Snowdon set a precedent that would carry on for decades.

-Princess Anne and Captain Mark Phillips, Charles and Diana, Andrew and Sarah Ferguson -- they all honeymooned on the yacht.

It was said that Diana loved swimming in the sea off the royal yacht, and that when she did that, she would go off one end of the yacht and all the crew, to protect her modesty, would very respectfully be down the other end of the yacht.

-But the marriages forged on Britannia would ultimately have another thing in common.

-It did become very obvious that all of these marriages ended in divorce.

And so, there was a saying going around that maybe, you know, she is the cursed ship for honeymoons.

-Cursed or not, Britannia’s reputation for secrecy did not go unnoticed by government.

So, they assigned this floating palace a top secret role.

-Recently discovered papers reveal a fascinating story, which is that during the '60s, at a time when there was the very real prospect of some sort of nuclear war, that there had to be contingency plans.

-It was called the Python Plan.

The idea was to disperse very important members of the government and obviously royalty to different safe havens.

And for the Queen and Duke, this would be Britannia.

-The yacht would then sail up into different sea lochs in Scotland, and the yacht would just move around, dodging Russian strikes.

-Happily, the Britannia’s decades at sea were instead spent hosting royal trips and trade missions.

By 1994, she had traveled over a million miles, enough to circle the globe for every year she’d been afloat.

-After 40 years at sea, Britannia was beginning to get quite tired.

She needed, on top of the £10 million that it cost in general upkeep, an extra £17 million to make her seaworthy.

-The early '90s, of course, were very difficult years for the royal family, particularly difficult for the Queen.

The War of the Wales was going on.

The annus horribilis in 1992 was devastatingly bad for the monarchy.

That was shortly after almost the final straw of that year, which was Windsor Castle, a favorite home of hers, catching fire.

-I think the Queen realized that the royal family was in something of a perilous position.

So, she came up with a raft of solutions to that, one of which was to open Buckingham Palace up to the public in a way to raise funds to pay for the renovations and restorations of Windsor Castle after the fire.

Another was a new tax regime, and the last thing she decided to do, which was clearly the most painful for her, was to give up the royal yacht.

-Although outwardly, the Queen was willing to part with the royal yacht, behind the scenes, she was hinting that she wouldn’t say no to a new boat.

Later, we’ll reveal how the plan to save the floating palace was sunk... -Prince Philip said that intervention had made a complete [bleep] of the whole thing.

-...and why dying in a palace doesn’t necessarily mean resting in peace.

-The farmer who was digging the grave spent the night going wild with the corpse, cutting off its arms and stabbing it with an iron pole.

♪♪ -The crown’s palaces are symbols of a nation and hallowed sites of royal ceremony, and few sites are as important as the most significant balcony in the land, though it’s not the one you might think.

-Buckingham Palace's balconies are world famous crowds gather to get a glimpse of the royal family as they emerge on major festival occasions.

But this humble building of five arches is a much more important balcony.

In fact, it’s crucial to the monarchy.

And it’s at St James’s, where, at the death of any monarch, the Accession Council meet to discuss the terms of transfer on the principle of rex nunquam moritur, "the king never dies", and all of the assembled dignitaries process onto this balcony to make the proclamation to the nation of the inheritance of the crown.

[ Trumpets playing ] -The Prince Charles Philip Arthur George is now, by the death of our late sovereign of happy memory, become our only lawful and rightful liege lord, Charles III.

-♪ God save the King ♪ -Buckingham Palace may be where the monarchy lives, but St James’s is where the crown resides.

-In royal parlance, St James’s Palace is the most senior of all the palaces, officially of higher rank than Buckingham or Windsor.

Not that you’d know it by looking at it.

-St James’s Palace is a bit of a conundrum or an anomaly, almost.

Certainly, it doesn’t look like what we think today a palace should look like.

-You can see from the turrets and crenelations over the top, it speaks of defense.

It looks something like a castle, but then it’s got later Brick buildings added either side of it, creating a jumble so it forms part of a streetscape.

You stumble across St James’s, and that seems a million miles away from the drama of Windsor Castle on its hilltop, or that processional avenue that leads to the front of Buckingham Palace.

And you have to ask why.

Why is this one the senior amongst the royal palaces?

-To work out this mystery, we have to trace its past, beginning with its construction by the royal family’s most prolific palace builder.

-Henry VII developed an appetite for building as his reign wore on.

In the end, he had something like 70 properties.

Amongst them was St James’s Palace, and he developed this from 1531, which is a crucial time because that’s when he forged his relationship with Anne Boleyn.

It’s before she became queen, but while she was his mistress.

The implicit hope for their partnership was that they would create a legitimate son and heir when she was proclaimed queen.

And the big threat to looking after a son and heir was the age of plague that could wipe out Henry’s desires, his hopes and aspirations for a future son and heir.

So, St James’s was chosen because it was removed from London, also Westminster and the busyness of court life.

Instead, it was surrounded by fields and fresh air, a place safely away from disease, and therefore, it was by all evidence, a nursery palace.

-St James’s Palace was simply a safe place to keep an heir.

The number one palace was half a mile down the road at Whitehall, until one fateful night in 1698.

-Whitehall had been the most magnificent palace in Europe, rivaling the Vatican in size, but then it burnt down, and once it burnt down, that left St James’s in prime position.

-It doesn’t have the splendor, the grandeur, but it does have the location perfect for visiting ambassadors, for foreign dignitaries, for foreign royal families.

-So, our royal family moved in, and for more than a century, monarchs used St James’s as their main London home, adding to it piecemeal, though never falling in love with the place.

-What you get then, going down the decades, is increased levels of mumbling and grumbling that this isn’t a place fit for a king.

-The role of St James's Palace diminishes, really, as royal tastes, even public tastes, change, this desire increasingly for coziness and privacy.

St James’s Palace is just not that kind of place.

George III moves his family into Buckingham Palace, which is far more to his liking, more opulent, more cozy, and Queen Victoria, who really is the monarch who brings in this whole idea of domesticity and the middle class family, she doesn’t want St James’s Palace.

Buckingham Palace and Windsor are far more to her liking.

-But whilst Victoria moved the family, many of the key parts of the job stayed at St James’s, and so did its status as senior palace.

-St James’s was useful, well positioned, and so it retained a function as a place of royal administration, its surviving state apartments perfectly useful for receptions.

So to this day, ambassadors are received at the Court of St James.

-To keep the senior palace plugged into royal life, it maintains a cutting edge system of communication.

Cutting edge for the 1840s, that is.

-Every morning since 1843, a horse-drawn broom, as it’s called, a carriage delivers the mail from Buckingham Palace over to St James's Palace, and this routine is followed religiously every day.

-Many royal traditions go back even further, like a royal yacht, a must-have for the monarch since 1660.

But a long history doesn’t guarantee survival, and by 1994, the future of the Queen’s floating palace, Britannia, hung in the balance.

-Things were pretty tricky in the country in the early '90s.

I mean, things were very difficult for the royal family, but they were very difficult for everyone else because we were in the recession.

Money was extremely short.

It was a very delicate situation for the Queen.

She was well aware that the public image of a royal yacht was not going down too well.

She let it be known that she was willing to give up the royal yacht.

Willing is quite different to accepting it willingly.

It was a huge sacrifice for her because she loved that yacht, and she didn’t really want to part with it, but I think she felt that in view of the public scrutiny that was going on, of everything to do with the royal family, she had to make that gesture.

-But documents from the National Archives suggest this wasn’t the whole story.

-Publicly, the palace was making sounds, noises that it was okay for the royal yacht to be relinquished.

Behind the scenes, though, there was a lot of lobbying going on saying that, "Well, actually, the Queen would very much appreciate a new royal yacht," but they didn’t want this to come out because they knew it would be a PR disaster.

-Unfortunately for the Queen, one politician was listening, and decided to get involved.

Things were made worse when the Defense Secretary then, Michael Portillo, decided to put his two pennyworth in, saying that there should be a new royal yacht and that’s what a future conservative government would do.

This was obviously very contentious because it should not be a party political issue, and it forced the Labour Party to take the opposite view, and that made things even more difficult for the royal family.

-The Queen will have realized that as soon as the debate around the royal yacht and its future became a political hot potato, it was time to drop the whole thing.

-The royal family were pretty annoyed about Michael Portillo getting involved and making this a political issue.

That’s the last thing they wanted.

And Prince Philip made that very clear, actually, to his biographer some years later.

He said that Portillo’s intervention had made a complete [bleep] of the whole thing.

-Portillo later suggested his attempts were at least appreciated by Her Majesty, but what’s undeniable is the intervention failed and Britannia’s decommissioning was scheduled for the end of 1997.

-People were confused as to why the end of a yacht’s life would mean that the Queen, who had been in many, many more distressing situations before, would choose that to show emotion.

But that actually doesn’t tell the full picture.

This yacht represented the Queen’s own reign, her father’s death, her legacy as a monarch.

It represented really a lot of what she thought of herself as a monarch.

-It’s a bitterly cold day, and a band's playing "Auld Lang Syne."

The camera's focused on the Queen having tears in her eyes, but I was there that day.

Just to the to the right was a grandstand full of 2,000 ex-royal yachtsmen and their families, and most of them were in tears as well.

-After the ceremony, Queen Elizabeth stepped on board Britannia for the last time.

-She took a final tour around her haven, her home that she had loved for more than 40 years.

The clocks on board Britannia all stopped at one minute past 3:00, which is the time she stepped off her beloved home for the last time.

Now moored in Edinburgh as a tourist attraction, the ship remains the last of 84 royal yachts, ending a tradition of more than 300 years.

♪♪ Britannia’s end was at least dignified, a far cry from the fate of one queen who perished at Sudeley Castle.

♪♪ ♪♪ -You might think of palaces offering the ultimate sanctuary in life and in death, but this isn’t always the case, and it certainly wasn’t the case for Catherine Parr.

In September 1548, Catherine Parr, Henry VII’s sixth wife and queen, dies at Sudeley Castle.

She had outlived the king, but only to die the year later.

But being royal doesn’t guarantee a restful afterlife.

During the Civil War, Catherine’s grand tomb was smashed up and the coffin behind it was lost.

But by the 18th century, gravespotting had become rather popular, and two ladies in 1782 went hunting for Catherine’s grave and finally found her.

They were so thrilled, they actually unwrapped the body.

They were shocked to see her perfectly preserved features begin to decay.

They hastily wrapped her up, but that wasn’t the end of the depredations that Catherine would suffer.

A few years after that, someone else got Catherine out of her grave and danced with her body, played with it, and left it exposed on a heap of rubbish.

The vicar found out and said it had to be reburied.

However, when it was reburied, someone was seen snooping around the grave, so the decision was made to dig a much deeper grave to stop these grave tourists.

But the farmer who was digging the grave got completely drunk, and it was said, basically spent the night going wild with the corpse, cutting off its arms, knocking out its teeth, and stabbing it with an iron pole, and then burying the coffin upside down.

It wasn’t for another 50 years until Catherine was properly laid to rest.

Her remains by this point was apparently a pile of powder, but they were buried in a spacious vault in Sudeley Castle and never disturbed again.

-Coming up, Kate needs to make a good impression when she meets the Queen at Windsor Castle... -The Queen didn’t like her.

She could veto any future potential marriage.

-...and the indignity of giving birth in a palace.

-The Queen’s body was a public possession, and everyone was going to go in to have a good old look.

♪♪ -Royal palaces are above all about family.

They exist to house and defend a dynasty, and dynasties require new blood.

In 2008, Windsor Castle would host the first meeting between the Queen and her grandson’s girlfriend.

-So, William and Kate had split up.

William split up with her thinking, you know, it’s too much, too early, and when they got back together in early autumn 2008, William promised that this time it was serious and that they would get married.

-For Kate, meeting her boyfriend’s gran wasn’t just a polite thing to do.

It was the law.

-Under the Royal Succession Act, the first six people in line to the throne do have to get permission from the monarch before they can marry.

If the monarch doesn’t like the girlfriend, the marriage is not going to happen.

So big stakes.

-Until recently, the monarch would have known any potential bride, as they all came from the aristocracy.

-It used to be that you would only marry into the royal family if you were already a cousin, or sort of somehow associated with it.

With Diana and Fergie, they were both related to ladies-in-waiting and polo players.

They would have already met over the years anyway.

That’s how they got to know Prince Charles and Prince Andrew.

-These days, of course, things have changed, and so many of the young royals are marrying so-called commoners, so they’re not part of that aristocratic circle who move together and know one another over a long period of time.

-So, Kate’s formal introduction to the Queen was a modern phenomenon, and she would be the first prospective fiancée to face it.

-Kate first met the Queen in the autumn of 2008 at Peter Phillips’s wedding at Windsor Castle, and this was huge because not only was she meeting William’s granny, harmonic for the first time, but at this point, William and Kate weren’t even engaged.

-Kate would have been under enormous pressure to make a good impression.

She had to meet the Queen, she had to carry it off well, and she also knew that William wasn’t going to be with her.

He was thousands of miles away in Kenya at his ex-girlfriend's.

And of course, there were going to be photographs and lots of press attention, which would have meant that it was going to be on record forever.

-Kate would face her daunting solo meet with the Queen after the ceremony.

-The reception was held at Frogmore House, which is a big grand house within the estate of Windsor Castle.

-And whilst other guests could let their hair down, Kate would need her guard up.

-She knew that it was a big deal.

I mean, after all, if the Queen didn’t like her, she could veto any future potential marriage to Prince William, so she knew the stakes were high.

She had to curtsy at the right time, make sure she said "mahm", not "mawm", and make sure she addressed her in the right way.

All these small little bits of protocol she had to get right first time because there was no room for error.

-It must be incredibly daunting to walk into your partner’s family, and especially if it’s the royal family.

I mean, how scary would that be?

-Kate was probably having her heart in her mouth, wondering when and if she was going to be able to speak to the Queen, and the Queen, knowing that she had to do this as well, she found an opportunity to come across and speak to Kate in a group of other people.

-She said later, the Queen was very friendly, so it was a brief, courteous first introduction.

-Ah, well, of course, Kate Middleton performed brilliantly.

I always think Kate’s a bit like a swan -- smiling serenely and calmly on a calm lake.

Underneath, the feet are paddling furiously.

She always looks as if she’s calm and controlled, even if perhaps inside, she’s not feeling it.

I think this performance of hers, when she was meeting the Queen, and this situation showed what inner steel and inner grit she really has, and I think it probably reinforced his opinion that she could deal with all the public pressure that came with marrying the heir to the throne.

-If Kate thought becoming a Windsor was like living in a goldfish bowl, it was nothing compared to royal life over the channel at Versailles.

Here, even the most private of royal occasions had an audience.

♪♪ -Today, royal wives give birth in hospital, but in the past, royal babies were born in palaces.

But this didn’t mean privacy.

In 1778, the French queen Marie Antoinette was about to give birth to her first child.

It was an incredibly exciting moment because the poor queen had been eight years without a child, and now the first baby was coming, possibly the next king.

Marie Antoinette went into labor and the bell was rung, and this bell was rung to signal that everyone should crowd into the Queen’s chamber, because a Queen’s birth was not private, it was public.

The reason why birth was so public was firstly to say, "Well, the child is legitimate.

Everyone saw it being born.

No pretenders.

This is the actual monarch of the future."

But the main reason was because it was an actual event.

It was a party.

It was a moment really that showed how important you were in the court, if you’d seen the monarch, the next child being born.

Marie Antoinette had 200 people watching her give birth, nothing more to show that the Queen’s body was completely a public possession and everyone was going to go in to have a good old look, including two chimney sweeps, who tried to get a better view from higher up.

And it has to be said that the most well sought-after spot to stand in was at the business end of childbirth.

So the poor queen, having the highest courtiers, the highest politicians who she dealt with every day, crowded round her nether regions, watching the birth.

After a 12-hour labor, she gave birth to a small girl.

Everyone was disappointed it wasn’t a boy, so they started chatting, and they were so busy socializing, they didn’t notice that the poor queen -- exhausted, overwhelmed -- she has a seizure and faints because of the press of people.

They’re too busy treating the Queen’s birth chamber as the latest cocktail party.

-The magnificence of Versailles is a long way from the hodgepodge of St James’s.

In 1698, this palace became the royal’s London HQ by default after a fire at Whitehall, and they set about a long series of improvements.

Most strikingly, George II commissioned a new front door, though not quite where you’d expect.

It’s half a mile away.

-This very grand entrance building built just off Whitehall is Horse Guards.

It was constructed between 1750 and 1759, really as the front door to St James’s Palace.

You wouldn’t guess that today, but back in the 18th century, you’d pass through this arch, across the park, and the palace would be before you.

You needed an ivory pass to be able to get through, and today, you still need a pass to drive a vehicle through.

-George was adding a vital layer of security to his palace, and above this giant front door, there is said to be a reminder why.

-If you look at the clock beneath the dome on Horse Guards, you’ll see a dark splotch next to the Roman figures for the number two, and that’s supposed to represent the time when Charles I was executed in January 1649, across the road from Horse Guards, at the banqueting house in Whitehall.

It could be a secret reminder of why royal architecture is created -- to protect the monarch and not participate in their downfall.

-On the other side of this palace front door, George II retained the vast open space that already existed.

-The reason there are no buildings on this vast area dates back about 500 years to a tiltyard, which Henry the Eighth built here, and he would charge horses up and down this arena.

People would flock to come and see the spectacle of Henry jousting against his leading nobles.

-This space became the ideal base for a new unit of elite mounted palace guards.

-The Household Cavalry was founded by King Charles II at Horse Guards, and the reason that he established that military unit was essentially a form of self-protection, because his father, after all, had been overthrown and executed in front of the banqueting house, and there had been a period with no monarchy.

-George II housed the men and horses in buildings either side of St James’s front door, and there they stayed, elite bodyguards, always ready to defend the crown.

Well, almost always.

-At Horse Guards, every day at 4:00, there is what’s called the dismounting ceremony, sometimes known as the Punishment Parade, and its origins lie in 1894, when Queen Victoria expected to be received by her disciplined guards, when in fact they’re all just drinking and gambling, and so, furious, she put on them a 100-year regiment of being inspected daily.

And so, it carries on past 1994, when it should have expired.

That means that you can still see it today.

It’s living tradition now.

-Coming up, Buckingham Palace’s secret Russian treasure... -Not even the czar would know exactly what was going to come out.

-...and the dastardly palace plot to kill a queen out for a ride.

-When the Queen touched the pommel with her hand, she'd then transfer her hand to her face and then poisoned herself and die a terrible death.

♪♪ -When it comes to collecting, few do it like the royals.

They have amassed the world’s largest privately owned art and jewelry collection, worth over £10 billion, and some of these treasures are specially designed to hide secrets, like their hoard of priceless Russian eggs created by Peter Carl Fabergé.

-Fabergé eggs are widely recognized as some of the most exquisite objects in the whole world.

Not even the czar would know exactly what was going to come out of each year’s Fabergé egg.

The only requirement was that they were unique and that each one contained a surprise.

And it is this uniqueness that makes each one so very valuable.

-The royals hold the world’s largest Fabergé collection, with pride of place going to the Colonnade egg.

-The Colonnade egg is absolutely stunning.

We start off with a green bowenite colonnade, and this then supports the pink enamel egg at the top.

And then surmounting this egg, we have a little Cupid figure.

-Around each of the columns are these silver gilt female figures, and then in the very heart is a perfectly working rotary clock made by Henry Moser & Cie, one of only four Fabergé eggs to include one of these very special working mechanisms.

-The whole thing is an allegory of the imperial family.

The two platinum doves that we see represents the czar and the Tsarevich, and then down below them, we have their four daughters, and Cupid represents the newborn Tsarevich, Alexis, and actually, this is what the egg is really all about.

These guys have been waiting for a son for a long time, and they were going to celebrate it with this amazing Colonnade egg.

-It was commissioned by Czar Nicholas II in 1910 as a gift for his wife, the Tsarina Alexandra, at a cost of 11,600 rubles.

That’s an expensive Easter gift.

-But it was just this sort of extravagance that was causing rising anger amongst an oppressed Russian people.

-The Russian Revolution of 1917 put an end to the royal family permanently.

The Fabergé eggs had become symbols of extreme wealth and were packed up and put into storage, hidden away in dark vaults, never to be returned.

-Revolutions aren’t cheap, and the regime really needed all the money they could get, and they knew how expensive these eggs were.

-In fact, the Soviet authorities allowed nine Fabergé eggs out of the country, and these included some of the finest examples -- the Coronation egg, the Rosebud, the Lily of the Valley, and the Winter Egg.

The Winter Egg sold in 2002 at auction for over £6 million, making it the most expensive egg in the world.

-The Colonnade was one of this nine-egg treasure trove.

In 1931, Queen Mary decided to purchase it as a gift for her husband, George V, and it’s been in the Royal Collection ever since.

-We don’t know how much Queen Mary paid for it because there isn’t any receipt.

It may have even come into the Royal Family’s hands as a gift, but it ends up in the Royal Collection alongside three other Fabergé eggs -- the Twelve Panel, the Basket of Wildflowers, and the Mosaic.

-And so, it remains largely hidden from public view, but we are granted an occasional sighting.

-The Colonnade egg was last displayed to the public during the summer opening of Buckingham Palace in 2012, where it appeared in the Royal Fabergé Exhibition alongside the other three Fabergé eggs.

Unfortunately, it’s now hidden away alongside so many of the amazing secret treasures that belong to the royal family, but aren’t usually seen by the public.

-As centers of wealth and power, royal palaces have long attracted conspirators, some with deadly intentions.

♪♪ -Royal palaces can be places of schemes and plots.

You are never safe as a monarch, even in your palace.

In the late 16th century, Elizabeth I was so concerned about attempts to kill her, she actually founded the early version of the Secret Service, who were always watching and looking for plots against the Queen.

One of the most intriguing plots is that of one Edward Squire, who plots to kill the Queen while she’s out riding.

Edward Squire was a stable hand who'd worked for Elizabeth at the Queen's stables at Greenwich Palace.

Then he was dismissed.

Apparently, he was so annoyed at this, he used his insider knowledge to conjure a dastardly plan to kill the Queen by putting poison on the pommel of her saddle, and when the Queen touched the pommel with her hand, she'd then transfer her hand to her face and then poison herself and die a terrible death.

It didn’t work.

The Queen didn’t die.

She didn’t even get sick.

The plot was a failure, and perhaps it had never really existed.

Edward Squire was probably set up by a paranoid secret service who were looking for enemies everywhere, a victim of the country’s obsession with plots.

Whether Edward did it or not, he was hung for high treason.

None of the plots against Elizabeth I worked.

Elizabeth I died in her bed in her palace in 1603.

-Elizabeth’s Greenwich Palace was demolished in the late 1600s.

But there is still one Tudor palace in royal use, and it has helped shape the capital, from its strangely placed front door on Whitehall to its former garden, now St James’s Park.

Even the games monarchs played here have left their secret mark.

-One of London’s most famous streets owes its name to St James’s Palace and the games played here by royalty and high society.

It was apparently James I of England who introduced the game pell-mell into England in the early 17th century.

It was a popular French game then, and it owes its name to the Italian pallamaglio, which means "ball hammer," and as that suggests, it’s a bit like croquet.

The difference is it’s played on a long alley.

Charles II built a pell-mell alley in St James’s Park, but the game soon fell out of favor, and so the alley gave way to the street that bears its name.

Today, pell-mell has become Pall Mall.

-As St James’s Palace grew in significance, the rich and their hangers-on flocked to new buildings around Pall Mall, and St James’s became a byword for aristocratic vice, as satirized by the artist William Hogarth.

-Hogarth’s print here shows St James’s Palace In the background.

You see streets of aristocratic buildings, gentlemen’s clubs.

You see the culture of self-advantage, of political dark dealing, gambling.

All of human immorality was here.

You see the judgment of God with a bolt of lightning pointing directly to where the cause of Britain’s current ills were.

It is at the court of St James.

-The lightning bolt never came, and today’s legacy of St James’s Palace is one of the grandest, most expensive areas of real estate on earth.

-Just a stone’s throw from St James’s, you find houses like this.

This is Bridgewater House, built for the Earls of Bridgewater.

The reason that the aristocracy clamored to take up these plots is because they themselves wanted to be close to the center of court.

St James’s, as the premier royal palace, has a magnetic pull.

-Next time, we have an exclusive interview with the man that took a bullet for Princess Anne... -He fired the other gun and it went into my abdomen, so that more or less was me.

-...Victoria and Albert are on a mission to pack Osborne with the latest technology... -It’s the kind of thing you’d expect to see in a house maybe a hundred years later.

-...and the secrets nobody talks about at a royal wedding.

-This is a shocking invasion of privacy, and royal brides found it terrifying.

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