Peaky Blinders' Cillian Murphy teases "dynamism" brought by Barry Keoghan as Tommy Shelby's heir

Of the many great additions to the Peaky Blinders cast for new movie The Immortal Man, one which caused particular excitement among fans was Barry Keoghan.

The Saltburn and Banshees of Inisherin star instantly seemed a perfect fit for the Peaky world, especially when it was confirmed with the release of the film's second trailer that he would be playing Tommy Shelby's son Duke – who had previously been introduced towards the end of the TV show's run (played then by Conrad Kahn).

The two Irish actors share a fascinating dynamic in the film, with their characters not always enjoying the most ideal father/son relationship, and speaking exclusively to Radio Times at the film's world premiere in Birmingham earlier this week, Murphy revealed why Keoghan had always been the top choice for the role.

"I've known Barry for a long time, and I've just watched him go from strength to strength," he explained.

"He's got that incredible unpredictability when you put a camera on him, that dynamism, so we were delighted to have him in the film. He was always our first choice."

For his part, Keoghan recently joked in an interview with Empire that he looked "more Cillian Murphy than Cillian looks Cillian Murphy", asking: "Go on, be honest – who’s got bluer eyes?"

Interestingly, given the on-screen relationship between the pair, Murphy had actually phoned Keoghan asking if he wanted to be part of the film on Father's Day – and he was instantly on board.

"At the drop of a hat, I was like, f***in’ yeah, anything to work with yourself again, and to become part of that universe and that world," he said.

The pair had previously worked together on Christopher Nolan's film Dunkirk back in 2017, and both have enjoyed huge success since then, with Murphy famously winning the best actor Oscar for a later Nolan film, Oppenheimer, in 2023.

Duke was introduced in the final season of the show as a thief whose existence Tommy had previously been unaware of, and in the time between then and the opening of the film he's risen through the ranks – now leading the Peaky Blinders with ruthlessness and brutality.

Peaky Blinders: The Immortal Man is in select UK cinemas now and will be available to stream on Netflix from Friday 20 March 2026 – sign up from £5.99 a month. Netflix is also available on Sky Glass and Virgin Media.

Add Peaky Blinders: The Immortal Man to your watchlist on the Radio Times: What to Watch app – download now for daily TV recommendations, features and more.

Check out more of our Film coverage or visit our TV Guide and Streaming Guide to find out what's on. For more TV recommendations and reviews, listen to The Radio Times Podcast.