In the volatile, high-stakes world of a French nuclear power plant, Gary, a young and transient laborer played by Tahar Rahim, finds dangerous work and a precarious new family. Hired as part of a team of contract workers who brave radioactive zones, he is drawn into a tense fraternity led by the seasoned Gilles (Denis Menochet) and finds himself irresistibly, recklessly attracted to Karole (Léa Seydoux), the live-in partner of his own colleague. Directed by Rebecca Zlotowski, this simmering drama explores the invisible contamination that seeps into lives, as Gary navigates the toxic environment of the plant and the even more perilous terrain of forbidden desire. Caught between the relentless pressure of the job and the escalating heat of his secret passion, he must confront the profound costs of both exposure and connection, where every choice carries a weight of potential consequence.