Martin has just turned fifteen and is taking off with his friend Line. A terrible accident will make him question everything, including his own existence. Haunted by her memories, her sister ChloÔe will go looking for her on the North Shore. Meanwhile, a drama in the forest will bring Martin closer to the mysterious snowman who has collected it. From that moment, the fate of the brother and sister will oscillate between the pain of inevitable separations and the intense joy of multiple reunions.