Gérard Kikoïne – Jouir! aka Sextasy (DVD version) (1978)
Frederic is a writer whose wife Alice is tormented by dreams of her promiscuous, but dead, sister who fell from their apartment, high in a tower block. Then someone falls from a similar apartment block near the dress shop where Alice works and she adopts the promiscuous ways of her dead sister, Norma, including seducing Frederic’s publisher and being caught in the act by Frederic. Frederic consults a psychiatrist and investigates her past which results in flashbacks of Norma’s behaviour. Alice’s new proclivities are exploited by Tony, the unscrupulous lover of the woman who introduced Alice to Frederic. He photographs her in a threesome and tries unsuccessfully to blackmail Frederic. Finally Frederic finds Alice’s former boyfriend and it turns out that he had been seduced by Norma and that Alice had caught them at it and pushed her sister off the balcony.