A young sailor finds himself trapped in the labyrinthine mansion of his occultist uncle, along with a number of eccentric and mysterious relatives who all seem to be harboring a dark secret.

Malpertuis is a labyrinth where characters issued from the Greek mythology are made prisoners by Cassavius. He manages to keep them (as well as his nephew and niece) as prisoners even after his death, through a binding testament. As the nephew unravels the mystery, we find out he cannot escape the house because Malpertuis is far more significant than we were led to believe.—Flávia Dietrich