Middle-class Princeton University student Tom Townsend, an admirer of Charles Fourier, attends a debutante dress ball one evening on a whim. After the ball, a mix-up leads to his meeting a small group of young Upper East Side socialites known as the Sally Fowler Rat Pack, after the girl whose apartment they use for after-hours parties. Believing that they accidentally stole a taxi from Tom, they decide to invite him to their after-hours party, to prevent ill feelings.