Amuck!

A young woman named Greta gets hired as a secretary for a famous novelist and his wife on a remote island near Venice. Her true motive is to investigate the mysterious disappearance of her lover, Sally, who was the previous secretary. Greta soon finds herself ensnared in the couple's decadent and perverse world, becoming the object of their erotic desires and the centerpiece of a sinister, unfolding murder plot where reality and fiction dangerously blur.