The opening episode transports us back to the late 18th Century, when the building first came into royal hands. Alexander Armstrong discovers that, originally, it wasn't a palace at all – but a private country house built by a man called the Duke of Buckingham. With red brick walls and a mere 40 rooms, "Buckingham House", as it was known, looked nothing like the imposing palace we see today.

But in 1761 the modest country pile caught the eye of King George III and his new bride, Queen Charlotte. The royal lovebirds purchased it as a rural retreat where they could raise a family and throw raucous parties. Raksha Dave gets glammed up, Georgian-style, to find out about the gossip and scandal that dominated the first balls thrown at Buckingham House – meanwhile JJ Chalmers hits the dancefloor to trial some fancy footwork to impress the queen.

Soon, King George and Queen Charlotte started making their mark on their new home. Alexander reveals how the Palace's gardens became home to the first zebra to ever set hoof in England – as well as an impressive underground ice house, the fridge-freezer of its day. But the building still lacked some facilities we consider essential today… toilets. Raksha discovers how one of the most prestigious jobs at Buckingham House involved carrying the king's portaloo – a role rewarded with a princely salary of £240,000, in today's money.

Later in the episode, JJ whips up some surprisingly appetizing Parmesan Ice Cream beloved by Buckingham House's first royal residents, and Raksha sniffs out the stinky yet sustainable solution to emptying the palace's cess pit.

Throughout, a CGI floorplan shows how the royal couple utterly transformed the house with massive extensions. But trouble was on the horizon. Soon madness and greed would drag the palace to the brink of destruction…

In this episode, the palace is in the grip of the Victorian Era – but as the mood swings from joy to heartbreak, what will become of Britain's most iconic royal residence?

We begin in 1845. Life in the palace is a fairytale for loved-up newlyweds Victoria and Albert. But with four tearaway toddlers roaming the palace corridors – and plans for many more children – the fast-growing family demands more space. Victoria adds some 200 rooms to the palace, including an entire new wing at the front and the iconic central balcony. But as the Palace grew bigger, so did the number of people required to keep things running smoothly. JJ Chalmers discovers what life was like for Victoria and Albert's servants, thanks to an extraordinary palace census taken on Sunday 30th of March 1851.

Despite the small army of staff patrolling the corridors, Buckingham Palace was terrifyingly vulnerable to intruders. JJ unlocks the tale of a notorious palace prowler who was rumoured to have stolen Queen Victoria's knickers! Meanwhile, Raksha Dave finds out what was involved in a royal homebirth at the palace – including the curious role of a crowd of bureaucrats, tasked with verifying the baby's bloodline.

Raksha tracks down the first flushing toilet installed at the palace – and JJ struggles to learn Victoria's favourite Waltz. But in the winter of 1861, tragedy struck when Prince Albert died at the age of only 42. Overwhelmed by grief, the queen fled Buckingham Palace, and the building that had given Victoria and Albert so many happy memories was left deserted.

The future of the abandoned palace hung in the balance. Alexander reveals how the government persuaded Victoria to return for the palace's first ever public garden party in 1868. The mood at the palace continued to be sombre, but there was a light at the end of the tunnel - and soon, an unprecedented celebration would bring the palace back to life…