Victor and Joan Smiley have been married for nearly twenty years and live in Brighton on England's south coast. They have no shared interests, only two friends and no children - just a cat called Gregory, who does not like either of them! Victor gets most of his fun at a sex club called the Kitten Parlour, and Joan has taken a lover, a very fit local taxi driver called Don.
Victor spends much of his time thinking about how nice it would be if he could simply get rid of his wife and start a new life with Kamila, who works at Kitten Parlour. So he develops a foolproof plan to slowly poison her with cyanide. What he does not know is that Joan is also thinking up a plan to murder him with Don's help! Which of the plans will succeed? Read on to find out!