There are moments in the Channel 4 drama Boy Athat are just pure cinema. This unfalteringly tense character-driven thriller tells the story of an ex-con called Jack (Andrew Garfield), his tentative attempts at rehabilitation and his desperate need to keep hidden the secret of his crime. Jack was involved in the murder of a young girl when he was himself only a child (like the Jamie Bulger killers), and now the tabloids and the vigilantes, aware of his release but unsure of his adult identity, are baying for blood.

All of this unfolds in lavish wide-screen style. Film frames have rarely been this artfully composed, light rarely this delicate. Here a moody shadow-filled shot of Jack in his attic looks like a nod to the classic Robert Mitchum noir The Night of the Hunter, while a flashback scene of the young killer dashing across a pedestrian bridge comes straight out of Truffaut’s Jules et Jim. Even the drama’s cross-cutting back to the pivotal murder has structural hints of Once Upon a Time in the West.

It’s no wonder then that the movie has been wowing audiences at film festivals around the world, or that the Hollywood mogul Harvey Weinstein recently bought the film for distribution in American cinemas. Which is clearly good news for the movie’s up-and-coming star Andrew Garfield and for its tyro director John Crowley, but it also begs one obvious question: what, exactly, is it doing on the telly?

“We never expected it to be released theatrically,” says the 38-year-old Crowley, who made a splash in 2003 with his stylish directorial debut, the Dublin-set Colin Farrell comedy Intermission. He says that Channel 4 pitched him the script, which was coincidentally written by the Intermission scribe Mark O’Rowe, and that from the start he was under no illusions that he was making a movie for the multiplex. “We always knew it would be a television film, but that doesn’t mean that we shot it like something that was [adopts derogatory tone] ‘just for television’. No, we shot it like a movie first and foremost. And now the fact that it’s been picked up by the Weinsteins and playing in festivals is just a bonus – because some of the more composed shots play beautifully on the big screen.”

Crowley explains that Boy A’s difficult and dark subject matter and its lack of a big-name star meant that it would have been virtually impossible to finance in the cash-strapped film sector. “It’s really brutal out there, right now,” he says. “Film financiers want all sorts of guarantees, yet there’s no such thing as a guarantee in film. So if the material is in any way marginal or unusual, like Boy A, or if it’s not like last year’s hit movie, then you’re in big trouble.”

Crowley, however, isn’t the only movie director turning back to the small screen. The much-admired Stephen Frears nips back and forth, depending on the film-making climate. His Blair-baiting TV drama The Deal was followed by two populist theatrical movies, Mrs Henderson Presentsand The Queen.Yet his next film is the upcoming TV drama Skip Tracer.

Similarly, Michael Winterbottom has enjoyed mainstream movie success with comedies such as 24 Hour Party People and A Cock and Bull Story, yet returned to television for smaller, difficult films such as The Road to Guantanamo. Ditto for provocative dramatists such as Ken Loach and Stephen Poliakoff. The American Neil LaBute ( In the Company of Men), who bombed badly with the multiplex turkey The Wicker Man last year, is now working on a satirical reality TV-inspired movie, to be shown on Channel 4 next year.

Crowley says that the old distinction between high-class cinema flicks and low-rent TV dramas no longer exists. “When you look at Frears, look at television in the US – where directors and actors are queueing up to work on The Sopranosand Six Feet Under– then you know that TV has shed its old image.”

Crowley, from Cork, Ireland, broke into film via a successful career as a London theatre director. He served an apprenticeship under Sam Mendes at the Donmar Warehouse. He directed Into the Woods and, appropriately enough, Tales from Hollywood, and was soon made associate director by Mendes.

He says that he always wanted to be a film-maker but that, after a philosophy degree, he drifted into theatre because movies seemed too glamorous and fanciful. When O’Rowe’s Intermissionscript eventually reached him he knew it was time to make the break. “I remember turning up on set on the first day of filming, which was, of all things, a car chase with Colin Farrell. I remember looking around at everyone and thinking, ‘If I f*** this up I may never make another film.’ It was totally terrifying, and yet thrilling, too.”

He will return to the big screen for the Michael Caine drama Is There Anybody There? Set in a 1980s retirement home, it stars Caine as a foul-mouthed magician who develops a close friendship with a young boy who is obsessed with spirits and the afterlife. It is, says Crowley, “wonderfully witty and deeply moving.” After that there’s another movie on the way, a historical epic called Star of the Sea with 19th-century merchant ships, mass emigration, mid-Atlantic storms – and big production values.

So does this mean that, despite all the fine talk, he has actually turned his back on TV for good? Or would he deign to come back to the small screen? “Yes, of course,” he says. “What’s not to come back to? Given that it’s so hard to get films financed, I’d rather spend my time working on good material in television than spending three years developing film features. And you can get the finance, and you can get the bolder material on the box easier than you can on the big screen nowadays. So if it was the right piece I’d go back to television. No question.”

Boy A, Mon, Channel 4, 9pm

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