Innocents with Dirty Hands (1975)

Saint Tropez, 1975. Julie Wormser and her lover, writer and neighbour Jeff Marle, plan the assassination of her wealthy husband Louis, an impotent who drinks a lot. She hits him, and leaves the rest of the task to Jeff. Julie finds herself alone the following day, and becomes therefore prime suspect. Where is Louis' body? Where is Jeff? Is there any secret beyond a door?