Waldo, a fêted filmmaker, is confined by old age and ill health to his London apartment. Frail and frustrated, he is cared for by his lovely younger wife, Zee. But when he suspects that Zee is beginning an affair with Eddie, 'more than an acquaintance and less than a friend for over thirty years', Waldo is pressed to action: determined to expose the couple, he sets himself first to prove his suspicions correct - and then to enact his revenge.