Spotlight on a Murderer

When the terminally ill Count Herve de Kerloquen (Pierre Brasseur, Goto, Isle of Love) vanishes without trace, his heirs are told that they have to wait five years before he can be declared legally dead, forcing them to devise ways of paying for the upkeep of the vast family chateau in the meantime. While they set about transforming the place into an elaborate son et lumiere tourist attraction, they are beset by a series of tragic accidents if that's really what they are...