Drawing on ideas from the psychoanalytic thought of Bion and the philosophy of Whitehead the paper explores the difference between ‘prehended lust’ and perverse sexuality. Prehended lust is regarded as life-enhancing whereas in perverse sexuality excitement is generated to disencumber the individual of anxiety. This view is illustrated by clinical material and by a more lengthy discussion of the recent British film The Principles of Lust, directed by Penny Woolcock.