Hélène Vincent (Three Colors: Blue) delivers a tour de force performance as a retiree with a secret past in the sly puzzler When Fall Is Coming (Quand vient l’automne). With an all-around excellent cast, prolific French director François Ozon (Swimming Pool, 8 Women) has crafted an intriguing tale—co-written with Philippe Piazzo—that gradually reveals clues to an overarching mystery, right up to the finale. Questions of familial responsibility and guilt weave through multiple characters as the story propels forward at a satisfying tempo.

Michelle (Vincent) lives a quiet life in the Burgundy countryside, foraging for mushrooms with her best friend, Marie-Claude (Josiane Balasko), cooking from the bounty of her extensive garden, or reading until she falls asleep with a novel in hand. She eagerly anticipates visits from her adoring young grandson, Lucas (Garlan Erlos), who resides in Paris with his mother. But when her daughter, Valérie (Ludivine Sagnier), brings the boy over for a holiday, Michelle is met with seething contempt and a rudeness that hints at a lifelong resentment.

At the table, Valérie remains focused on her phone throughout the multi-course lunch Michelle has enthusiastically prepared. Though Michelle struggles to remain gracious, her generosity is apparent: She turned her Paris apartment over to her daughter, who is so audaciously mean that she comes across as completely abrasive.

Later, Michelle and Lucas take an idyllic walk, hand in hand across a little bridge, with a waterfall and autumn’s full glory in view. Cinematographer Jérôme Alméras captures the beauty of golden light filtering through colorful leaves, as well as the warmth of Michelle’s rustic home, filled with personal mementos and a crackling fireplace.

Upon their return, they discover that the side dish of wild mushrooms has landed Valérie in the hospital. Surely it was an accident that poisonous mushrooms were served… or was it? Earlier, Marie-Claude had spotted false chanterelles during their foraging. Can wishing for something make it a reality? Or was the poisoning deliberate?

Tout de suite, mother and son depart for Paris. Since Valérie can no longer trust Michelle, Lucas is barred from ever seeing her again. Heartbroken, Michelle begins sleeping during the day, slipping into depression. Her doctor recommends volunteering to lift her spirits.

Meanwhile, she forms an unexpected bond with Marie-Claude’s son, Vincent (Pierre Lottin), who has recently been released from prison for an unspecified crime. With maternal affection, she hires him to work on her grounds and encourages his dream of opening a bar—unlike his mother, who sees him as a disappointment. When he meets with Valérie to persuade her to mend their fractured relationship, the encounter leads to a dramatic off-screen incident, adding another layer to the mystery. Like a sleight-of-hand artist, Ozon plays with contradictions and even the paranormal, deepening the film’s intrigue.

Clad in colorful sweaters and high boots, courtesy of costume designer Pascaline Chavanne, Michelle is a stylish presence who commands the screen with understated charisma. At times, she’s energetic enough to pull invasive weeds; at others, she is transfixed, contemplating the possibility of senility. Her expressions are beautifully nuanced as she confronts long-buried truths. In the autumn of life, Michelle is a wholly believable aging woman—having lived fully, but not without regrets.

When Fall Is Coming will have its U.S. theatrical premiere on April 4 at Film Forum in New York. (See it twice to catch the small moments that shape the story’s intricate arc.)