The extraordinary Perry Mason never handles simple divorce cases, but this one is a strange bird. Rita Swayne is dating her sister's ex-boyfriend. Her sister, Rosalind, is married to shady insurance adjuster Walter Prescott, who's got dollar signs in his eyes and ice water in his veins. When Rita's beau gallantly steps in to warn Rosalind about her heinous husband's designs, Prescott hatches a plan to prey on them all... by suing for big profit.

For Mason, this case should be a lark. But when a murdered man is found in the Prescott home -- and a nosy neighbor sings an incriminating song about illicit love and a hidden gun -- legal eagle Mason suddenly finds himself defending a sitting duck.