Jim "Lucky" Moore (Allan Jones (actor)), an insurance salesman, comes up with a novel policy for his friend, Steve (Robert Cummings): a 'love insurance policy', that will pay out $1-million if Steve does not marry his fiancée, Cynthia (Nancy Kelly). Encouraged by Jim's argument that Jim has never had to pay out on a policy so that the marriage is a sure thing, Steve accepts. The upcoming marriage is jeopardized by Steve's ex-girlfriend, Mickey (Peggy Moran), and Cynthia's disapproving Aunt Kitty. The policy is Underwriting by a nightclub owner, Roscoe (William Frawley), who sends two enforcers - Abbott and Costello - to ensure that the wedding occurs as planned. Everyone involved in the situation winds up sailing or flying to San Marcos (a fictional South American country), where another complication arises, when Lucky falls for Cynthia. Lucky winds up marrying Cynthia, but Roscoe does not have to pay the $1-million because Steve ends up marrying Mickey.