Ralph Martin, a playboy, must give up all his girlfriends when he becomes engaged to his beloved Dolores Winkle. Since he has stayed late at a goodbye dinner given by these other gals, he arrives late and drunk to the Winkle home, where an engagement party was held. The butler escorts him to a bedroom, where it turns out would-be girlfriend Toots is sleeping; she screams and rouses the household. Jumping to the obvious conclusion, Dolores breaks their engagement. Ralph is so unhappy he decides to make a dangerous flight over the Pacific. Ralph's plane goes down and he loses all contact with the outside world. A plague called masculitis strikes, killing only men. Dr. Prodwell searches for a cure, but to no avail. Then a pilot tells Dr. Prodwell that she has found a man on a Pacific island. The women decide to keep the valuable discovery a secret, but a woman gangster finds out about the last man's existence. Soon, all the women in the world are after Ralph, and Dolores must do ...