The play has a cast of six: Frank and Fiona Foster, Bob and Teresa Phillips, and William and Mary Featherstone. The well-to-do Frank and Fiona have a polite and emotionally distant relationship, while Fiona is in a secret affair with Frank's employee Bob, whose marriage with Teresa is very stormy; she feels neglected by him, and her suspicions are heightened by ghost phone calls. The contrast between the nature of the Fosters' and Phillips' relationships is heightened by the visual difference in their respective living spaces and furnishings, both of which co-exist in the same space on the stage. Asked where they have been, both Bob and Fiona lie to their spouses that they have been comforting, respectively, William and Mary Featherstone, each of whom is alleged to believe their spouse to be having an affair.
The Fosters and the Phillips have each invited the Featherstones to dinner on successive evenings, with both being played out simultaneously on the same set, the Featherstones shifting back and forth between them; William is revealed as a very controlling husband who systematically intimidates Mary. Teresa and Bob's conflict culminates in her throwing soup at him but mistakenly hitting William, while in the Fosters' dinner party, his drenched state is the result of a leak from the bathroom above.
Teresa, whose marriage with Bob is on the rocks, visits the Fosters and discovers Bob and Fiona's affair. In Teresa's absence, Mary visits the Phillips, and while Bob is in the next room, she answers a phone call from Frank, leading him to believe that she and Bob are having an affair. He tells William, who goes to the Phillips' house and physically attacks Bob but is knocked out by Teresa. After Frank invites everyone to his house to clear the air, William half-apologises to Mary, who chews him out over his controlling nature, but ultimately forgives him, while Bob and Teresa make up.
When they are alone, Frank forgives Fiona after she admits to having cheated. Although she does not reveal with whom, Frank thinks he has worked it out, and calls Bob, but Teresa answers. Assuming that he was the ghost caller, she suggests meeting him in private to discuss his problems, to which he bewilderedly agrees.
