Steven Knight explains how Peaky Blinders film ended up quite different from his initial plans

Peaky Blinders boss Steven Knight has long been clear that he wanted to bring Tommy Shelby to the big screen – but it turns out that the plot of new movie The Immortal Man wasn't the first idea he'd had for a cinematic spin-off.

Speaking exclusively to Radio Times at the film's world premiere in Birmingham earlier this week, the prolific screenwriter revealed that while he always envisaged the Second World War as the setting, he hadn't been so sure exactly what story he wanted to tell from the conflict.

"Well, the first idea was quite different," he explained. "It was always going to be Second World War, but then it sort of evolved.

"This was from the first series, I wanted to do Second World War," he added. "But then it changed a bit. And then I started to research a bit of Second World War stories that hadn't been told. And then the plot started to come from that.”

The particular Second World War story that makes it into the film is the true tale of Operation Bernhard, a Nazi Germany scheme to win the war by flooding the UK with counterfeit bank notes and breaking the economy as a consequence.

In the movie, Tommy Shelby's son Duke (Barry Keoghan) is recruited by Nazi sympathiser Beckett (Tim Roth) to help with the scheme, but of course it isn't long before Tommy returns from his self-imposed exile to intervene.

Speaking to Radio Times at the premiere, Murphy admitted that he had never heard of the operation before Knight presented the idea for the film and said he was impressed by the way the writer "always picks these obscure parts of history and weaves the Peakys into it".

Speaking further about Operation Bernhard at a Celebrating Peaky Blinders Q&A at the BFI a week before the film's release, Knight explained: "They got people at Sachsenhausen concentration camp – people there were selected because of previous work that they'd done – and they got them to forge something like 350 million pounds of British currency.

"The first plan was to just drop it from planes," he added. "[But] they then thought that they would do it through criminal organisations. People who wouldn't ask the question about, 'Is this a good thing to do? Is this a patriotic thing to do?'

"And it was all obviously kept secret, but the Bank of England stopped people using 10 and 20 pound notes from 1942 at the end of the war. They changed the design of most bank notes because there were so many of these forged bank notes in the currency. But of course, it was a massive, great big secret at the time.

"But it's true, and so what I've done is taken that as sort of a starting point... or how did that not happen?"

Knight had previously explained during an interview for the Radio Times Writer's Room that when he had first set out to write the show, the one thing he knew was that he "wanted to take it between the two wars."

He continued: "So I wanted to begin when First World War ends and end when the Second World War begins. Covid had a say in it because series seven had to be scrapped.

"So instead of ending it at the Second World War, in series seven, we've made a movie which is out very soon and is fantastic, which takes us up to the Second World War."

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.

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