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Columbo: 9x4

Rest in Peace, Mrs. Columbo

Columbo unwittingly becomes part of a deranged woman’s diabolical plot to destroy the two men she believes responsible for her husband’s death in prison. After murdering one, she moves in on the other, Columbo, to kill the person closest to him, his wife.

Columbo: Season 9 Episode 4
Mar. 31, 1990