For some reason, British actor Aaron Taylor-Johnson seems to be best at playing unhinged Americans, so the part of drug addict James Frey is a good fit. He's also co-written the screenplay with his wife, director Sam Taylor-Johnson (Nowhere Boy, Fifty Shades of Grey), based on the book by Frey. At first billed as a memoir, the story has since been repackaged as fiction after questions arose about certain details. This adaptation takes Frey's tale at face value, presenting a narrative that's familiar but broadly effective.

We meet Frey high as a kite, running naked through a party, jumping out of a window and waking up on a plane a doctor has carried him onto. His brother Bob (Charlie Hunnam) checks him into a residential rehab clinic. Interactions with the opposite sex are forbidden, but this place is full of rule-breakers, so James is soon having illicit meetings with the vulnerable young Lilly (Odessa Young). Their courtship is quietly compelling, and this helps you root for Frey despite his infractions. The lack of background on the source of his addiction is frustrating, though, you may find yourself waiting for a revelation that never comes.

What's most remarkable here are the performances: Billy Bob Thornton is tremendous as seasoned patient Leonard, while every brief moment of counsellor Juliette Lewis is worth waiting for. Giovanni Ribisi is great in an otherwise questionable role of a predatory gay man. Films set in institutions often thrive off a variety of darkly comical, dramatically intense characters – think of One Flew Over the Cuckoo's Nest or, recently, The Miseducation of Cameron Post. While this more derivative film isn't up there with those greats, it's got enough of the key ingredients to entertain and make you think.

General release from Fri 30 Aug.