Dangerous Number: Hank Medhill, artificial silk manufacturer, has returned to the U.S. from Japan to learn that his former girlfriend, Eleanor Breen is about to marry. Hank convinces Eleanor to leave the groom-to-be and marry him. Shortly after the marriage, they discover that they have nothing in common. They separate. Hank decides to pick any name from the phone book and date them. That date results in a wild and frightful night for Hank, thanks to Eleanor's clever plan.