Based on the eponymous memoir by journalist David Sheff, Beautiful Boy makes good on its saccharine title. Felix Van Groeningen’s adaptation, although also inspired by a book written by Sheff’s son, Nic, is indeed more about the father and how he perceives his child, than about the child himself. Playing the elder Sheff, Steve Carell pursues his dedication to serious films and proves to be a good casting choice for the role of a tender and attentive father who used to be close to his son. Timothée Chalamet is just as well-suited to play Nic, not only because he is, indeed, beautiful, but also because he fits the bill of the teenager who only seems perfect and perfectly happy. As Chalamet’s turn in Lady Bird — playing the emo and cool heartthrob Kyle — made clear, he has a self-awareness that doesn’t feel fake, but is instead lived in and true to the anxious self-discovery that defines puberty. In Beautiful Boy, Nic’s drug addiction allows Chalamet to add an extra layer to this growing and typically shaky identity.

Time seems to break into pieces when David discovers the extent of his son’s problem and of his lies: Nic took crystal meth much more than one single time. Van Groeningen asked his frequent editing collaborator Nico Leunen to help him rework the film’s structure after feeling stuck, and the results are Beautiful Boy’s best asset. Flashbacks are fragmented across images of the present time as family pictures and places remind David of Nic at his best, when the world seemed to have its arms wide open to this happy and gifted child. The pop music soundtrack, if sometimes overbearing, flows through those different time periods to try and unite them in a continuity, highlighting the difficulty for David to do so himself. He can’t reconcile teenage Nic with the little boy he once was.

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Although David tries to figure out what went wrong and when, the film itself is tactful enough not to present a simple, single explanation for such a complex issue as drug addiction. Every failed attempt at helping Nic, every sacrifice that David and his new family make, as well as those of Nic’s mother, slowly reveal just how unknown the mechanics of meth addiction are. Beautiful Boy occasionally veers into prevention video territory, but the despair and forced acceptance that David goes through show a side of fatherhood that cinema rarely confronts. Sometimes, your child has to help himself. Carell still can’t help sounding like Michael Scott from The Office when he raises his voice, but his natural softness is wrecked by David’s decisions in a beautiful way, and gives dimension to this character.

The same can’t be said of Nic, who remains frustratingly unknowable throughout. The fact that his illness is by nature difficult to understand, although making for powerful moments of incomprehension for David, can’t excuse this lack of definition. Shades of an interesting protagonist appear in Nic’s self-hatred and in the moments where Van Groeningen dares to show what the teenager gets out of drugs: the thrill and the sense of freedom, however sinister their origin, are real emotions that narcotics allow him to access. The tying together of addiction and puberty in a simultaneously harrowing and sensuous sex scene when Nic reconnects with his ex-girlfriend leaves a confusing taste that makes his dilemma more vivid than ever — but doesn’t give him more of a personality. Ultimately, Beautiful Boy doesn’t quite succeed in making the Sheffs’ doubts and despair resonate because Nic remains too vague a character, a token good teen to represent what teenage addiction can do — to the addict, but also, and more powerfully here, to those who love him.

Manuela Lazic (@ManiLazic) is a French film critic based in London, UK. She regularly contributes to The Ringer, Little White Lies Magazine and SPARK. Her work has also appeared at The Film Stage and the BFI, among other publications.