Dunkirk's Fionn Whitehead: "A lot has happened that makes me feel older than I am"

You could say that: it was a little thing called Dunkirk, directed by a plucky up-and-comer named Christopher Nolan. The Second World War picture was an ensemble piece – Tom Hardy, Kenneth Branagh, Mark Rylance and former One Direction star Harry Styles were in the cast. But it was Whitehead’s face on the buses and the billboards, his eyes every bit as piercing as those of his more established co-star Cillian Murphy.

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As the pale-faced British soldier Tommy, he got to say the opening line (“English! Anglais!”) as well as deliver Churchill’s “We shall fight on the beaches” speech, reading it aloud haltingly from a newspaper in a later scene. Not bad for his first film.

Whitehead is centre stage again in the new adaptation of Ian McEwan’s novel The Children Act, scripted by McEwan himself, which opens in cinemas on Friday 24 August. He plays Adam, a 17-year-old Jehovah’s Witness with leukaemia, whose parents are in court fighting the doctors who want to give him a blood transfusion that’s forbidden by their religion. The judge, Fiona Maye (Emma Thompson), visits Adam in hospital, where she develops an emotional connection with him; they even sing an impromptu duet when she notices a guitar at the end of his bed.

“That’s my dad’s,” he tells me, eyes shining proudly (his father is jazz musician and composer Tim Whitehead).

There may be no trudging through wet sand in military clobber this time, but The Children Act was anything but tranquil. “It was draining. There’s never a scene where he’s having a relaxing cuppa or going to the allotment to pick carrots.” And Whitehead gets another dramatic entrance. Though nearly half the film has elapsed before we meet Adam, that time is filled largely by other characters praising him as “special” and “profound”; the build-up is almost as tantalising as the one famously given the Godot-like Hickey in the play The Iceman Cometh (filmed in 1973).

In McEwan’s novel, we learn that Adam had “set in motion a fascinating drama in which he starred in every scene”.

Whitehead, whose maroon polo shirt, skinny jeans, white socks, black shoes and silver earring lend him a certain Mod look, nods emphatically.

“Ian really captures that age where you think you’re the star. It’s Adam’s way of dissociating himself from reality. Being a Jehovah’s Witness teenager, he’s less desensitised by the world, so when Emma’s character tells him what his decision entails, it’s the first time he’s had to face this thing he’s been avoiding.”

The actor visited a Kingdom Hall – a Jehovah’s Witness place of worship – near his London home as research. “I lied about why I was there,” he says with a guilty shudder. “I felt terrified they’d find me out. They were so welcoming, and that helped with Adam because I could see how it would be attractive.” And once the service started? “It’s a religion that’s quite…” He searches for a tactful word before settling on “intense”.

He also prepared for the role by writing in character. “It was so useful. Adam’s someone who would write these lengthy theatrical poems and diary entries rather than texting.” Does he still feel close to that age himself? “A lot has happened in those four years that has made me feel older than I am.”

At 17, fresh from London’s Richmond College, he applied to a number of drama schools, all of which turned him down. He took odd jobs – childminder, barista – and sent off his CV and photo, which led to a successful audition for a part playing a boy with telekinetic powers in the 2016 ITV drama Him. “When I got that, my boss at the coffee shop grabbed a couple of beers and we toasted. Then I turned around to a sink full of washing up.”Dunkirk'sast-forward a year or two and he was answering questions about Harry Styles’s haircut at the Dunkirk premiere. Indeed, if you want to see Whitehead at his most amusingly incredulous, check out the clip below where an interviewer on the red carpet asks if he is heartbroken about the pop idol’s shorter locks: “Er, I don’t have an emotional connection to his hair,” he says after a moment’s disbelief. Reminded of that now, he cringes. “My knee-jerk reaction is to be sarcastic, but my agent said it comes across as arrogant.”

He will next be seen in Roads, a Morocco-toEurope road movie. But Dunkirk still looms large. Ask how life has changed thanks to that $525 million-grossing blockbuster, he says, “I got a good flask out of it.” He shakes the item in question, his morning coffee sloshing around inside. “I sometimes cover up the film logo so people don’t think I’m a bighead: ‘Oh hi, I’m Fionn – you know, from Dunkirk?’ But I’m proud of this.” He marvels at it, passing it from one hand to the other. “It’s a really sturdy flask.”

Ryan Gibley

The Children Act is due to be released in UK cinemas on 24th August 2018