Florinda Bolkan plays the daughter of a prominant English politician who keeps having recurring "nightmares" in which she makes love to a bisexual nympho who lives downstairs and conducts all-night LSD orgies. When the nocturnal wet dreams become murderous, the neighbor turns up dead, and Florinda is the main suspect. Did she actually commit the murder she dreamt about? Is she being framed by her philandering husband? Did Florinda actually make nightly visits downstairs aside from borrowing the occasional cup of sugar?