Ian McKellen and Helen Mirren on gender-flipping Gandalf in 'Lord of the Rings'

Sir Ian McKellen and Dame Helen Mirren appear together in the gripping new thriller The Good Liar, but if Mirren had her way, they would have starred opposite each other sooner. The actress has expressed regret she wasn’t in Peter Jackson’s The Lord Of The Rings films.

But Dame Helen might have her chance on Amazon’s new Lord Of The Rings series, especially with one of the Middle Earth stars calling for female wizards in the new show.

"Those old legends, those old mystical stories, they're so based within a patriarchal landscape," actress Robyn Malcolm, who portrayed Morwen in The Lord Of The Rings: The Two Towers, explained to New Zealand’s Stuff. "Why not look at the magic of a matrilineal world where the magical powerhouses are women?"

Read more: Lord Of The Rings actress wants Amazon’s Gandalf to be a woman

But would Mirren get the opportunity to play the iconic wizard? Not if McKellen gets there first.

“I’ve been waiting for the call, but now it’s to be a woman… I’m up for playing a woman,” McKellen jokes.

“That’s the way to go, really,” Mirren agrees.

“You’re not going to play Gandalf are you?” McKellen asks.

“No, of course I’m not! No-one could out-Gandalf Gandalf, could they? It’s impossible. He was the uber-Gandalf, the Gandalf to end all Gandalfs.”

“Is Gandalf in it?” McKellen asks. “I don’t know if it’s before… He’s seven thousand years old in the version I did, he may be younger than that, in which case I wouldn’t be appropriate casting.”

But let’s hope that Mirren gets to play one of the new characters – she’s clearly a big fan of the series.

“I was watching the first scene,” the actress tells McKellen, “literally yesterday. I was flicking through the channels and there it was, the first scene of you arriving in Hobbit-land in the thing with your hat…”

“Over-acting… That was the very first day of shooting.”

“No! Not over-acting! Beautiful, funny, sweet, the whole character was there. It’s charming. It’s lovely.”

Speaking of great acting, twisty-turny thriller The Good Liar, which sees McKellen’s con man target Mirren’s vulnerable widow, is in UK cinemas now.