When an elderly neighbor in good health unexpectedly dies, a married Manhattanite (Diane Keaton) is convinced the woman's death was no accident. She ropes a few of her friends (Alan Alda and Anjelica Huston) into playing whodunit, despite protests from her skeptical husband (Woody Allen, who also directs). He doesn't believe it was murder, but he joins the investigation soon enough -- just to keep his marriage alive.