When Momo leaves his small home town to go to university, he is full of enthusiasm and confidence, but slowly the pressures of study and campus living begin to grind him down. Half way through his course he finds himself at a crossroads with both his relationship and studies.

Sister Hanna is a spirited, witty, resolute, warm-hearted, and - attractive nun. With her wit and street cred, she takes charge of Kaltenthal Cloister, transforming it into a popular refuge for all those seeking help of one kind or another. She also brings new life to the sleepy provincial community, proving herself quite a match for her great rival and opponent, the mayor Wolfgang Wöller.