Summertime, sunshine and always fun-time! That's what Bibi calls a perfect vacation at Martin's Farm. But why is Tina in such a bad mood? Maybe it has something to do with her boyfriend Alexander von Falkenstein? First, he doesn't have any time for her and then prefers to ride with the pretty Lena. Tina follows them and ends up entangled in a thrilling adventure from which only her friendship with Bibi and Alex can save her.