''The Cocoanuts'' is set in the Hotel de Cocoanut, a resort hotel, during the Florida land boom of the 1920s. Mr. Hammer (Groucho Marx) runs the place, assisted by Jamison (Zeppo Marx), who would rather sleep at the front desk than actually help him run it. Chico Marx and Harpo Marx arrive with empty luggage, which they apparently plan to fill by robbing and confidence game the guests. Mrs. Potter (Margaret Dumont, in the first of seven film appearances with the Marxes) is one of the few paying customers. Her daughter Polly (Mary Eaton) is in love with struggling young architect Bob Adams (Oscar Shaw). He works to support himself as a clerk at the hotel, but has plans for the development of the entire area as Cocoanut Manor. Mrs. Potter wants her daughter to marry Harvey Yates (Cyril Ring), whom she believes to be of higher social standing than the clerk. This suitor is actually a con man out to steal the dowager's diamond necklace with the help of his conniving partner Penelope (Kay Francis).