Léo is ten years old. He is a solitary poet who seems to have left the lightness of childhood behind him far too soon, to become buried in books. His encounter with 20-year-old Théo, a carefree young adult, forces him out of his shell. By becoming best friends, despite their age difference, both will help each other grow up. But this friendship isn't to everyone's taste and Léo's father decides to put a stop to it. Théo then leads Léo on an escapade to the seaside, at the risk of no longer being in control of the situation.