Mathieu is a marine biologist. He spends his time on his microscope, sliding tiny marine organisms corpses. He's unhappy. His true wish would have been being on the sea. An event will abruptly change his life : Christine, his mother in law, runs away. Impressed and touched by this impulsion, Mathieu starts looking for her. Far from everything, apart from theirs families, Christine and Mathieu will gather, understand eachother and share the same desire to take back theirs lives in control.