While viewers saw a young Prince Charles in the second series of the Netflix drama, played by Julian Baring, as he attended brutal boarding school Gordonstoun, this will be the first run to feature Camilla Parker Bowles, then known as Camilla Shand.
Emerald Fennell, who acted as head writer on the most recent series of Killing Eve, is playing the young Camilla while God's Own Country's Josh O'Connor will feature as Prince Charles.
Viewers will be introduced to the prince as a student at Cambridge and it looks likely the series will cover his coronation as the Prince of Wales in 1969.
The third instalment of the acclaimed series will cover the period from 1964 to 1977 as change sweeps Britain and the Royal Family must adapt to the altering world.
To portray this next chapter in the Queen's life, new actors will portray the Royals with Olivia Colman taking over from Claire Foy to play Queen Elizabeth.
Tobias Menzies has assumed the role of the monarch's husband Prince Philip from Matt Smith whilst Helen Bonham Carter steps into Princess Margaret's shoes following on from Vanessa Kirby's departure.
A trailer for the upcoming instalment has revealed the show makes reference to an older version of the Queen as she looks at a new portrait to be used on postage stamps.
An aide tells her the picture is "an elegant reflection of Her Majesty's transition from young woman to..." before she interrupts: "Old bat?"
"Settled sovereign... just the tiniest changes," the aide goes on.
The new series will launch on the streaming service on 17 November.