Antonio and Nikola are inseparable friends who live across the road from each other, and share a love of pyrotechnics and mobile phones. Their families have been in dispute for years over an easily resolvable problem: the water that flows from the top house to the bottom house. The boys’ friendship, as they are about to enter puberty, is put to the test at Christmas time when their families uncover much more dangerous secrets and interests, and the water just carries the hate of the adults to the children.