Mutz Hagedorn has just graduated from grammar school, much to the delight of her aunt Jenny, who cares for her like a mother. Then she learns from notary Strohbein that she has inherited the hotel “Zur Jungfrau” from her uncle, it is located on Lake Constance in Üttlisborn. On the way there, she meets the winsome Konrad on the train. Both have the same destination, only at the train station, their paths split. When she then stands before “her” hotel, she’s appalled. The “Jungfrau” is an old, dilapidated eyesore, because people with taste put up at the “Mönch”, which is owned by the Leitner family. Both families have been at odds with each other for years. Then, Mutz learns from Konrad that he as well is a Leitner and the owner of the “Mönch”. Now, she wants to be victorious, win the trial once and for all. Konrad accepts the challenge. Firstly, the “Jungfrau” is turned into a modern hotel in no time.