Modern-day thriller. It is the birthday of air hostess Maggie, who lives in a remote, converted windmill, and she has invited several friends over to celebrate. However, when the first two - old friend Ann and nearest neighbour Jenny - arrive, Maggie is nowhere to be seen. The two ladies discuss her fondness for men and associated peculiar tastes, including taping the most private intimacies between herself and her lovers. Both, it transpires, are nervous that Maggie may have turned her attentions to their men: Ann's fiance Steve and Jenny's husband Peter.
The atmosphere relaxes a little with the arrival of pilot Terry and local painter Andy, there to hang his latest nude portrait of Maggie. But then Steve staggers down the stairs, having been attacked with a Samurai sword, and dies at their feet. Listening to Maggie's tape, they discover that he has been sleeping with her - and so has Peter, who arrives soon after. As the police are due to arrive, they also discover Maggie's body, wedged into a cupboard.
Next day, after being charged with the murders, Peter hangs himself. That leads Jenny to confront Ann, who recently and only just survived an aircrash, with questions about her memory. Both women blame each other for the killings, but Jenny insists they should try to reconstruct the scene.
The following morning Terry returns to the windmill to collect his lighter and discovers Ann there, and Jenny's body in the cupboard where they found Maggie...