Lots of 15-year-old girls long for a fairy-tale prince to sweep them off their feet. Not Anna. She'd prefer to find her own path in life first, before some guy turns up out of the blue and turns everything upside down and inside out. But then one day, her brother Raoul comes home with a frog he caught nearby. Before Raoul torments the little creature to death, Anna manages to rescue it. Later, she remembers the old fairy tale about the prince who had been turned into a frog. In a light-hearted mood, she picks up the frog and actually kisses it… at which point something incredible occurs. The frog really is turned back into a prince - into Prince Dietbert von Tümpelberg, to be precise. Once Anna has recovered from the shock, she realises there are certain practical problems to be faced if you are suddenly responsible for a Frog Prince who’s a thousand years old. Raoul is the first problem; he starts plaguing Anna because he wants his frog back, but soon he becomes suspicious. Meanwhile Anna sets out to help Dietbert cope with life in the 21st century. So Anna is torn between mounting affection for the charming prince, though of course she would never dream of admitting it, and rage when he behaves again and again in the most infuriating way. For Dietbert himself though, far more is at stake as he attempts to win Anna's heart.