Nicholas (Timothée Chalamet) has been missing for a few days before he turns up, clearly at the tail end of a drug binge, and unable to talk to his worried father, David (Steve Carell) about where he has been. It’s the start of a predictable, maddening pattern and downward spiral.

So David takes his son to rehab. His son does well enough to get transferred to a halfway house. And then he’s gone, presumably using again. Upon each return, Nicholas looks further gone than before, until finally, he’s stealing from his own family to pay for his crystal meth habit.

Flashbacks determine that Nicholas comes from a loving, affluent home and, save for his parents’ divorce, there is no evidence of trauma or reason for the parental guilt that David struggles with throughout the film.

David, a writer for the New York Times, carefully researches his son's battle, consulting a doctor (Timothy Hutton) who explains that recovery statistics for crystal meth addicts are no better than single digits.

Lack of third act

Working with co-writer Luke Davies (Lion), Felix Van Groeningen adapts not one but two memoirs: Beautiful Boy: A Father's Journey Through His Son's Addiction by David Sheff and Tweak: Growing Up on Methamphetamines by Nic Sheff.

The dual protagonist structure allows for two tremendous performances that hang off nothing in particular. There's nothing Van Groeningen – the brilliant director who reinvented the weepie with The Broken Circle Breakdown in 2012 – can do to convince the viewer that this is a movie.

Although beautifully shot and ably performed, the lack of any kind of third act doesn’t even allow it to pass for a solid “disease of the week” picture. The female characters, meanwhile, are unwisely confined to the margins.

A disappointing anglophone debut from the talented Belgian auteur.