Arthur (Anthony Hopkins)'s marital difficulties with his wife Louise (Blythe Danner) suggest divorce, which could require that he pay a large sum in alimony. His imagination works overtime for the duration of the film as he arranges and rearranges scheme after scheme to kill Louise. As a defense attorney, he is familiar with both the courts and the minds of criminals. Deep in his own imagination, he bounces ideas off of himself (a double played by Donegan Smith), as he plays each murder, or the subsequent trial, through in his mind, searching for problems, loopholes, and the elusive watertight alibi.
Eventually his mistress Jackie Willis (Swoosie Kurtz) puts two and two together and confronts Louise in secret. They realize the gravity of the situation and immediately put together their own scheme to do away with him and make it look like suicide. Arthur, albeit at gunpoint, takes control of the situation, pointing out the flaws in the plan, poking holes in what was supposed to be a foolproof scheme. It turns out he had been cheating on Jackie, and while Louise was trying to murder him, he was being missed by a date, so suicide was out of the question.
Arthur was recording the whole situation to cassette. In exchange for not having to pay alimony, he will not bring the matter to court with the cassette as evidence. He escapes unscathed.
Louise is hysterical, her plan was supposed to work! She chases him with the gun, a brief struggle ensues, and she is shot dead. This is what Arthur wanted, sort of, but it was an accident. However, all evidence points to him now. The cassette was only a bluff, there really is no evidence on his side. He shot his wife; if Jackie, the only witness, testified it was only an accident, what jury would possibly believe it? Case closed. There is no hope for Arthur now. Then he stops imagining things, and Louise arrives home, shoots him dead, and phones Jackie to inform her that the deed is done.
Who does Jackie confront?
Louise