Prologue

Prince Karl Franz is heir to the Kingdom of Karlsberg. Raised within the rigid structure of palace life after the loss of his father, he has grown up sheltered from ordinary society under the guidance of tutors and military tradition. Though promised since childhood to Princess Margaret, he has never met her. Hoping to broaden his experience and prepare him for leadership, his grandfather King Ferdinand sends him incognito to the University of Heidelberg to live as an ordinary student. Accompanied by his beloved tutor Doctor Engel, the overly formal valet Lutz, and Lutz’s assistant Hubert, Karl Franz leaves court life behind for the first time.

Act I

In Heidelberg, life is vibrant, youthful, and full of freedom. At the beloved Inn of the Three Gold Apples, run by Herr Ruder, students gather nightly in celebration of friendship and university life. There, Karl Franz meets Kathie, Herr Ruder’s niece, whose warmth and spirit immediately capture his heart. As he settles into student life and forms close friendships with his fellow classmates, he experiences for the first time a sense of belonging and joy far removed from the expectations of royalty. Before long, Karl Franz and Kathie fall deeply in love, despite the impossible divide between prince and commoner.

Act II

As the school term continues, Karl Franz embraces the camaraderie and freedom of Heidelberg, growing even closer to Kathie and his fellow students. Their happiness is interrupted when Princess Margaret and her mother arrive with news that the King is gravely ill. Karl Franz is summoned home to fulfill his royal duty and proceed with the long arranged engagement to Margaret. Torn between love and obligation, he considers abandoning the throne for a life with Kathie, but Doctor Engel and the royal court remind him of his responsibility to the kingdom. Reluctantly, he agrees to return home, promising Kathie he will come back to her.

Act III

Two years pass, and Karl Franz has been unable to return to Heidelberg. Following the death of his grandfather, he has ascended the throne and now lives bound by the demands and ceremony of royal life. Princess Margaret, meanwhile, carries her own private disappointments and understands that Karl Franz’s heart has never truly belonged to her. When word arrives that Doctor Engel has died in Heidelberg, Karl Franz is persuaded to return for a reunion with his old friends, while privately hoping to see Kathie once again.

Act IV

Before Karl Franz arrives, Princess Margaret secretly visits Kathie. Realizing the sacrifices required by the crown, the two women agree that Kathie will tell Karl Franz she has fallen in love with another man and plans to marry him. Believing he has truly lost her, Karl Franz resolves to accept his royal responsibilities fully and move forward with Margaret. Though duty ultimately prevails, Kathie remains the great love of his life, and the memory of Heidelberg continues to live in his heart forever.