He is a ten-year-old boy, curious, dreamy and highly imaginative. He would be like all other little boys, if his entire life wasn't spent shut up in an impenetrable cellar with his parents, his two siblings and his grandmother, all horribly disfigured by a mysterious fire no one speaks of. But his family's hidden life is about to change: his sister has just given birth, the Cricket Man is lurking dangerously in the shadows and he is visited by some mysterious fireflies, whose powerful glow will inspire him to try and escape from the cellar in search of the truth.