The Crown Needs 300 Extras To Recreate This Iconic Royal Moment

The first of these new cast members to be announced was Olivia Colman, who'll be stepping into the Queen's sturdy patent courts as The Crown moves through the Seventies and beyond. This is arguably the biggest role yet for one of Britain's best-loved (and most versatile) actresses, who already has one Golden Globe to her name (earned for her supporting role in The Night Manager). She'll be joined by Helena Bonham-Carter, who'll embody Princess Margaret in her most turbulent years, while Tobias Menzies will be Matt Smith's replacement as Prince Philip. Newly announced as an addition to the cast is Ben Smith, who will play Anthony Armstrong-Jones opposite Helena's Princess Margaret.

Let the waiting game begin: the long process of re-casting means that production for the third season is set to begin in July, with a release date slated for 2019.

Tearing through a decade or so in just ten episodes, The Crown's characters are ageing at such a rate that the actors playing them just can't keep up. So, in the interests of verisimilitude (prosthetics and CGI trickery can, after all, only go so far) season three will inaugurate a fresh line-up of stars. While we're sad to wave goodbye to Claire Foy, Matt Smith and co, the promise of an entirely new cast is certainly one that'll keep us talking until the next season airs.

Season two closed in 1964, concluding with the birth of Elizabeth and Philip's youngest child, Prince Edward. The show's third round should pick up shortly after, with a storyline that will carry us through Harold Wilson's turbulent tenure as Prime Minister, which saw the UK gripped by economic crises and industrial strikes.

After teasing us with hints to the contrary, the show's producers have finally confirmed that we won't be introduced to Lady Diana Spencer in season three (despite the fact that the future Princess of Wales first met her husband-to-be aged just 16, when he was dating her older sister, Sarah) Whichever actress lands the coveted role will go on to take centre stage in season four, as the show starts to document her tumultuous marriage to Prince Charles; there are also rumours that the star could stay on into the fifth season. Let the casting speculation commence…

Peter Morgan, the show's creator, recently revealed that the next two seasons will be shot consecutively. 'We're doing them back-to-back. I'm writing them all at the moment,' he recently told the audience at a BAFTA Masterclass event. 'Now we're just embarking on the process of casting.'

There were three people in this marriage, after all: season three will also mark Camilla Parker-Bowles' Crown debut (appearing, presumably, alongside a re-cast twenty-something Prince of Wales). Charles and Camilla (née Shand) met and fell in love in the early Seventies, when they were part of the same posh countryside set. At the time, neither party was prepared to fully commit: Charles to a woman who didn't quite fit the mould required by the palace, Camilla to a life of royal rules and regulations.

We could trawl through the history books to pick out potential plot points for season three, one storyline which we can count upon is the disintegration of Princess Margaret's marriage to photographer Anthony Armstrong-Jones. 'We'll see the break-up of this extraordinary marriage between Margaret and [Lord] Snowdon, historical consultant Robert Lacey told Town & Country last year. The couple were married for the best part of two decades, eventually separating in 1976 and formally divorcing two years later, with multiple infidelities on both sides.

Last year, the show's producers applied for permission to carry out new building work at the show's Elstree base, which has now received a green light from the relevant authorities. This means Buckingham Palace will get new gates and a balcony that's primed for royal waves (does this mean a wedding tableau?), while Downing Street will also be extended.

It's been confirmed that Josh O'Connor, one of this year's nominees for the prestigious EE BAFTA Rising Star award, is set to play a young Prince Charles for seasons three and four (you might recognise from God's Own Country or ITV's The Durrells). In the announcement he said: 'I am thrilled to be joining The Firm for the next instalment of The Crown. Seasons 3 and 4 will follow some of the most turbulent events in the Prince of Wales's life and our national story and I'm excited to be bringing to life the man in the midst of it all. I'm very aware it's a formidably talented family to be joining, but reliably informed I have the ears for the part and will fit right in.'

He might be the heir to the throne, but it's not all about Prince Charles in season three: writer Peter Morgan has hinted that the Queen's only daughter, Princess Anne, could have some pivotal plotlines, involving her romance with first husband Captain Mark Phillips and the 1974 kidnap attempt outside Buckingham Palace. She'll be played by Erin Doherty, whose sole TV credit to date came in an episode of Call The Midwife last year.

Best known for her roles in Mr Turner and _Vera Drak_e actress Marion Bailey will be taking over from Victoria Hamilton to take on the role of Queen Mother. Here enthusiasm at joining The Crown cast echoed many of the other new additions. She said: 'It's a brilliant show and we have a tough act to follow but what a gift to be playing the fascinating and greatly loved Queen Mother.'