To celebrate his 23rd birthday, Jonathan organizes a party with his girlfriend, his best friend, and his younger brother on a remote, uninhabited island in the mouth of the St. Lawrence River. As the evening wears on and the four friends become progressively drunker, Jonathan, in a show of bravado, pitches the keys of the boat into the river. The following day, after a fruitless search for the keys, the four friends realize that they are stranded on a deserted island, with a few bags of chips and very little fresh water, out of sight of civilization.

Maxime Salomon, a rebellious policewoman, takes under her wing four young people with troubled pasts.