After a chimp follows Samantha and Tabitha home, Samantha turns him into a man to find out where he belongs. Harry, the former chimp, insists on living a man's life for just one day. At Darrin's office, Evelyn Tucker, and her assistant, Bobby Flynn, are searching for an ad symbol for Brawn, a new man's cologne. When Larry tries to stall until Darrin returns from Canada, Evelyn insists on waiting for him at the Stephens' home. Fascinated by Harry's simian antics, Evelyn decides he would be a perfect model for Brawn. Samantha declares that Harry must leave until Larry warns if Harry isn't in his office next morning, Darrin is out of a job. Samantha worries when Darrin phones he'll be away another two days. After posing all morning, Harry decides being a man is no fun. Larry phones that Harry's photos are great and plans a national tour for him. Harry, however, insists on becoming a chimp at once until Samantha advises him. After Harry turns the studio upside down and reduces Evelyn to hysterics, she fires him. Samantha applauds, explaining Harry was just launching Darrin's campaign for Brawn, based on the wild emotions it arouses. Evelyn feels it's sensational and Larry takes all the credit. Back with his owner, Samantha is sure the chimp will leave again.