Dominic West said he hopes the public give Charles the “benefit of the doubt” in the fifth season of The Crown.
The 53-year-old actor plays the then Prince of Wales, now the King, in the latest series of the Netflix royal drama.
Imelda Staunton also takes over from Olivia Colman as the Queen, with West and Elizabeth Debicki, playing Diana, being handed the baton by Josh O’Connor and Emma Corrin.
Speaking at a press conference on Tuesday, West said: “(Charles) is one of the most scrutinised, publicised lives in the world. So it’s hard to know what people know about him.
“This period covers a time when he (had) bad press.
“It was a divorce and there’s always two sides in a divorce (so) I suppose viewers heard one or the other.
“And hopefully there’s a bit of perspective now and I hope everyone gets a fair hearing. I think that’s part of the reason for doing it.
“I obviously love the guy and… inevitably, you take their side or you give them the benefit of the doubt and I hope that will maybe happen and people see Charles in this.”
The new series is set to cover storylines including Martin Bashir’s controversial Panorama interview with Diana and the subsequent media storm surrounding her relationship with Charles.
A young Prince William will be shown as a pupil at Eton, seeing his mother’s interview on TV, and Charles will reportedly be shown yelling and swearing in response to the broadcast.
Jonny Lee Miller follows in the footsteps of Gillian Anderson, who won a Golden Globe for her performance as Baroness Thatcher in the previous season.
The 49-year-old actor, best known for Trainspotting, said when he read more about the former prime minister, Sir John Major, he learned to “respect” him.
Him and Major both grew up in south west London surrounded by a theatrical family though Lee Miller admits his household was “very left wing”.
The ex-Conservative prime minister’s father was British music hall and circus performer Tom Major-Ball and Miller’s grandfather was actor Bernard Lee.
Miller said: “Really what anyone’s trying to do when you’re playing whoever you’re playing is you’re trying to…inhabit someone, you’re trying to sort of fall in love with them.
“So there’s always a fascinating journey, and especially with somebody I think has (been) very misunderstood, actually, and who I respect greatly.”
Another storyline is expected to show Charles cutting short a holiday with Diana to host a secret meeting with Sir John Major at Highgrove in 1991 in which they discuss potentially ousting the Queen.
The series has already faced criticism from the likes of Dame Judi Dench and former prime ministers Sir John and Sir Tony Blair as a result of its plotlines.
Last month, Netflix put a disclaimer in the description of its YouTube trailer for the fifth series of The Crown, saying the production is a “fictional dramatisation” and “inspired by real events”.
Jonathan Pryce who stars as Prince Philip, taking over from Tobias Menzies, also spoke of his sympathy for the late Duke of Edinburgh.
The 75-year-old actor said: “Looking at Prince Philip, it’s made me much more aware of the kind of man he was behind the headlines.
“I mean, he spent all his life, most of his life, getting bad press, as a kind of grumpy, irascible person who kept saying all the wrong things, usually in the colonies.
“And finding more about the man, who was behind all that spin, has changed my view of him.”
Netflix’s hit royal drama will return on November 9.