Peaky Blinders returns underground: the quiet power of Kelmarsh Tunnel and the weight of Arthur’s end

In the new Netflix film, peaky blinders steps into an enclosed, disused railway tunnel in Northamptonshire—Kelmarsh Tunnel—where the brick walls and remote quiet offered the production something rare: space to work, and room for the story’s shadows to feel real.

Why is Kelmarsh Tunnel central to Peaky Blinders: The Immortal Man?

Kelmarsh Tunnel, on the former Northampton to Market Harborough line, was used as a filming location for The Immortal Man, the latest instalment following the Shelby family. Director Tom Harper described the brick structure as “one of those treasures that you sometimes find when you’re filming, ” and said the enclosed nature of the tunnel helped the production film without many members of the public nearby.

Harper also framed the film’s scale as part of its mission: “We wanted to create a big story that felt like an event that people could come together to watch as an audience. ” He said a larger film budget meant the team could travel to “incredible places” and discover “little known gems. ” In practical terms, the tunnel’s remote location also meant fewer fans gathered to catch a glimpse of filming—something Harper said was not a problem there because it is “quite tricky to get into” and “quite enclosed. ”

The story itself returns to Birmingham during World War Two, with Oscar winner Cillian Murphy reprising his role as gang leader Tommy Shelby. Creator Stephen Knight has said the original series was set in Birmingham but mostly shot in Manchester, Leeds, and Liverpool—adding that “this time I thought it was really important to come home. ” Filming took place across Birmingham, while also extending into Northamptonshire.

What does the film reveal about Tommy Shelby’s return—and Arthur’s absence?

The Immortal Man is set in 1940 in Birmingham, where Tommy returns and “faces his most destructive reckoning yet. ” A synopsis for the film adds that “with the future of the family and the country at stake, Tommy must face his own demons, and choose whether to confront his legacy, or burn it to the ground. ”

For many fans, the emotional fulcrum is not only what Tommy does next, but who is no longer at his side. Paul Anderson, the actor who played Tommy’s brother Arthur throughout six seasons, spoke about his mixed feelings on turning the story into a film. He called the film “amazing, ” but said he was “slightly apprehensive” about the decision to make a movie, adding: “We made a good show, we ain’t made enough seasons – I think we should’ve just done a couple more seasons. I don’t see a reason to do a film to be honest. ”

Anderson also described a familiar tension in long-running, beloved projects: “It’s about what the fans think and if they don’t like it, we’re at the mercy of them. ” At the same time, he urged cinema-goers to expect a shift in how Arthur is perceived—telling audiences they would see “Arthur in a very different light. ”

Yet Anderson confirmed the turn that will land hardest for some: Arthur is not physically alive in the film. The character remains present in another way—living on in Tommy’s guilty conscience. Anderson said Stephen Knight gave him advance warning on this “sad” outcome, and he did not object to the direction, saying: “Well, what can you do eh? It is how it is. I thought I’d just leave them to it. ” He also described Arthur’s ending as “great, ” even if “sad, ” calling it “such a powerful thing to do. ”

When and where can audiences watch The Immortal Man—and what’s the larger bet?

The Immortal Man will be shown in selected cinemas before becoming available to stream on Netflix from 20 March. The push toward cinemas, Harper’s emphasis on a shared audience experience, and Knight’s insistence on returning to Birmingham all point to a single wager: that peaky blinders can still feel communal, even as it moves into a new format.

Kelmarsh Tunnel’s role in that wager is both logistical and symbolic. Harper talked about the “magic” that still clings to seeing a place on the silver screen, even in an era saturated with filming. The tunnel’s sealed-off quality helped the production stay focused; its rough brickwork and contained darkness also offered a physical metaphor for what the film asks of its characters—entering a confined place where the past echoes loudly, and there’s no easy way around what waits ahead.

Back in that same quiet tunnel, where crews could work with few onlookers, the film’s ambition comes into focus: an “event” meant for an audience, built from enclosed spaces, heavy decisions, and the kind of absence that doesn’t vanish just because a character does. When the lights come up in cinemas and, later, living rooms, the question left hanging is not only what Tommy Shelby returns to—but what returns with him. In peaky blinders, even the end of Arthur can keep walking beside the living.