sentences:  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 tunnels.