On an isolated island in Brittany at the end of the 18th century, an artist is commissioned to paint a young woman's wedding portrait.

A French family with two daughters, 10-year-old Laure and 6-year-old Jeanne, moves to a new neighborhood during the summer holidays. With her tomboy ways, Laure is immediately mistaken for a boy by the local kids and passes herself off as Mickaël.

Set during a sultry summer in a French suburb, Marie is desperate to join the local pool's synchronized swimming team, but is her interest solely for the sake of sport or for a chance to get close to Floriane, the bad girl of the team? Sciamma, and the two leads, capture the uncertainty of teenage sexuality with a sympathetic eye in this delicate drama of the angst of coming-of-age.