Robbie has a wonderful time going steady with two girls simultaneously -- a highschooler and a college co-ed -- until the two ladies compare notes one day and plot immediate revenge. They maneuver Robbie into dating the both of them on the same night.

Robbie and Katie have an unpleasant personality clash with the young couple who move into the next apartment in their building. Meanwhile, when Uncle Charley assures Dodie that Katie is her sister, she phones and leaves a message with Robbie. When he forgets to pass it on, a family crisis is not far away.