Lover Come Back (1961)

Jerry Webster and Carol Templeton are rival Madison Avenue advertising executives who each dislike each other’s methods. After he steals a client out from under her cute little nose, revenge prompts her to infiltrate his secret “VIP” campaign in order to persuade the mystery product’s scientist to switch to her firm.
Delbert Mann
Rock Hudson, Doris Day, Tony Randall, Edie Adams, Jack Oakie, Jack Kruschen, Ann B. Davis, Joe Flynn, Howard St. John, Karen Norris, Jack Albertson, Charles Watts, Donna Douglas, Ward Ramsey, June Wilkinson, Ted Bessell, William Benedict, Richard Deacon, Lovyss Bradley
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