Joachim Trier’s latest film, showing in Cannes in competition, follows the life of a young woman as she finds her way in the adult world. It’s a warm and intelligent film with a fine performance by its lead actress.

Julie (Renate Reinsve) is an A-grade student who starts out studying medicine before discovering the many things she’d like to be only to keep changing her mind. Her mother stands by her decisions – ‘as long as you’re sure’ – but the problem is that Julie is unsure about many things in her life. As she flits from one pathway to another, so does she change her partners. But when she meets a much older graphic novelist Aksel (Trier’s regular collaborator Anders Danielsen Lie), it looks as if at least one part of her life has found some stability.

The Worst Person in the WorldTrier has split his film into twelve chapters with a prologue and epilogue, each chapter containing key moments in this young woman’s life. Perhaps the most enjoyable and unusual of these is the chapter headed ‘Cheating’ in which our young heroine abandons her boyfriend’s book launch party and crashes a wedding reception, embarking on a flirtatious and wholly delightful night with Eivind (Herbert Nordrum). Other entertaining chapters involve Julie spending a weekend with Aksel’s friends and their kids, leading to the couple dealing with the tricky issue of their age difference and the question of whether they should start a family. A chapter in which Julie’s useless father is introduced is excellent with the boyfriend’s hackles rising and the father immune both to the hostility and the hurt he causes.

Trier’s technique is adept and polished throughout, but there are two stand-out scenes: one when Julie races out of her apartment and around town while the rest of the city remains motionless; the other is when Julie, Eivind and their friends take mushrooms, a hilarious and inventively envisioned trip. In fact, the film is constantly interesting not just visually but in terms of its content.

The Worst Person in the WorldTrier has laid bare a host of truths about what it means to embark on adulthood and all the pratfalls and problems it entails. Yet he also shows the flipside of that: the joy of self-discovery, the great love affairs, the right decisions as well as the wrong. Reinsve is more than capable of carrying this film as the young protagonist – surely this film will act as a springboard for an international career, should she want one – and she is superbly supported by her two male co-stars.

This is a coming-of-age film that will resonate with anyone who has been through their twenties and will leave you relieved that you survived them but a little nostalgic for those heady, scary and exhilarating days.