The zany plot follows nitwit Gracie Allen trying to help master sleuth Philo Vance solve a murder.

Jeffrey Haywood wants to marry to Virginia Embrey. However, Virginia refused to marry unless her older sister, the hard-to-please Angelica gets married first. Angelica, in turn, finds every man she knows too dull and predictable, and for this reason prefers to stay single. Jeff then tries to make Angelica interested in the mild-mannered and timid Reggie Irving passing him off as a notorious playboy to intrigue her. He asks his friend Polly to teach Reggie “how to treat a woman right”, but he turns to be a disastrous learner.

King Kong is brought in by the evil Dr. Who to dig for Element X in a mine when the robot Mechani-Kong is unable to do the task. This leads to the machine and the real Kong engaging in a tremendous battle atop Tokyo Tower.