Plot

The lives of the residents of a small French town are changed when thousands of the recently dead inexplicably come back to life and try to integrate themselves into society that has changed for them.

The recently deceased of an anonymous French town suddenly return to life, calmly streaming forth from a cemetery in a silent procession. The town council, led by the mayor (Victor Garrivier), makes plans to house the returned and help reintroduce them to society. The mayor informs the council that the event has lasted for roughly two hours throughout France, returning an estimated 70 million people to life nationwide (most of them elderly people), with more than 13,000 in their town alone, all of whom had died within the previous 10 years.

However, the reintegration poses challenges. "The returned" suffer from effects similar to those that may be seen after severe concussion, such as disorientation, sleep disturbance, and wandering. Former professionals among the returned are moved to menial jobs when it becomes clear that, although they can perform rote tasks, they can no longer engage in spontaneous problem solving or planning, and that even their apparent consciousness may be an illusion. This behavior adds to the growing sentiment that the returned are different from their former selves. However, while the returned generally function sluggishly during the day, a doctor named Gardet (Frédéric Pierrot) has become suspicious of the returned after observing some of them clandestinely attending animated meetings, conducted in the middle of the night, during which their symptoms seem to disappear.

Nonetheless, the returned reunite with their former loved ones: the mayor's wife who had died from cancer, Martha (Catherine Samie), with the mayor; a 6-year-old boy, Sylvain (Saady Delas), with his parents, Isham (Djemel Barek) and Véronique (Marie Matheron); a young man, Mathieu (Jonathan Zaccaï), with his wife, Rachel (Géraldine Pailhas). Rachel is initially reluctant to see Mathieu, until one day he follows her home, acting as though he never left. Rachel eventually accepts him, and the two make love. In addition to the nocturnal meetings of the returned, Gardet also observes the gradual reunion of Rachel and Mathieu with growing concern, but when he tries to warn her of possible danger, Rachel rebuffs him.

One evening a series of explosions tears through the town, apparently detonated by the returned in an act of mass sabotage but without inflicting any casualties. In the chaos, the returned head for a network of underground tunnels. The mayor attempts to stop his wife from leaving with the rest but begins to feel ill and, after Martha urges him to "give in", apparently dies, only to appear later in the tunnels among the returned. The military responds by gassing the returned with a chemical that induces a permanent coma.

After guiding some of the returned to the tunnels, Mathieu makes his way back to Rachel, and recounts to her the events leading to his fatal car accident. He reveals that he crashed the car while looking for her after the two had fought. Rachel follows him into the tunnels, tearfully kissing him before he disappears into the darkness. She returns to the surface and observes the military carting away the comatose bodies. The bodies are laid atop their graves in the cemetery and slowly vanish.