Young Prince Karl Heinrich has spent his entire life behind the palace gates protected from the world. He has been raised in a melancholy atmosphere of strict discipline and duty, yet he often looks out at the frolics of youths and maidens who live beyond the walls. When he passes his exams, Karl is sent to Heidelberg to complete his studies. It is a heady new world of brew, song, and comradeship. Karl falls in love with Kathi, a pretty barmaid, and she reciprocates. But can the love survive their disparate backgrounds? Will Karl ever find happiness or will duty deny it to him?