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.

Orson Welles
as Cassavius

Susan Hampshire
as Nancy / Euryale / Alice / Nurse / Charlotte

Michel Bouquet
as Charles Dideloo

Mathieu Carrière
as Jan

Jean-Pierre Cassel
as Lampernisse

Daniel Pilon
as Mathias Crook

Walter Rilla
as Eisengott

Dora van der Groen
as Sylvie Dideloo

Charles Janssens
as Philarette

Sylvie Vartan
as Bets