'Peaky Blinders' will introduce a "pretty dark" female character set to challenge Tommy Shelby.

Cillian Murphy as Tommy Shelby

Cillian Murphy as Tommy Shelby

Director Anthony Byrne has opened up about the upcoming sixth season of the BBC period drama and hinted at a mystery woman who will give Cillian Murphy's alter ego a "run for his money".

Speaking to Digital Spy, he said: "There's a great female character who is new, who is pretty dark. I haven't seen a character like her in 'Peaky' before.

"I won't say who she is, but she certainly gives Tommy a run for his money. She challenges him in a different way basically. She's certainly not a protagonist and I don't know if she's an antagonist."

While Anthony compared the character to Oswald Mosley - a real life politician played by Sam Claflin in series five - he admitted the team haven't actually cast the role yet.

He added: "It's similar to Mosley ... she has a similar ideology, and that's challenging for any character, like I've said before ... he or she, they don't have guns or a gang, but they have an ideology that's like a virus and it's more dangerous than anything.

"She's a great character and we're really close to casting her, as well."

But fans could have a long time to wait to see the new character appear on screen, as Anthony has revealed the sixth season could be delayed until the end of 2021 - or even early the following year.

He explained: "In an ideal world it would be great to be prepping again towards the end of the year with a view to start shooting early next year.

"That feels achievable, whether that's true or not, I have no idea.

"If we did start shooting in January (2021), we wouldn't finish until May or June and then it's another six months of editing."

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