Eggar, an English secretary with an international advertising agency in Paris, is asked by her boss (Reed, so sinisterly smooth that you know he's up to no good) to work overnight at his house. Next day, she agrees to see him off at the airport with his family, then drive his car back to the house. But finding herself heading in the wrong direction, she impulsively drives on - towards the Riviera and nightmarish happenings which include encounters with various strangers who apparently recognise her, assault in the rest-room at a service station, an interlude with an enigmatic hitchhiker (McEnery), and the discovery of a body in the boot of the car. Echoes of Psycho proliferate (including a visit to an old dark house), but the tortuous mystifications and ponderings (shakily shored up by the revelation that she sometimes suffers bouts of amnesia) wear out their welcome long before the final gush of explanations. The presence of Stéphane Audran, as Reed's glacially neurotic wife, makes one wonder wistfully what Chabrol might have made of it all.