The friends actually wanted to take it easy, spend a few vacation days at Mai's parents' vacation home in the mountains, hiking, lazing around and canoeing. But as Melinda is packing, she receives devastating news from Mai. Tofu has disappeared! Instead of taking the public transport, she had sent her dog ahead with Mai and her parents. And now he's disappeared! Again! But even this time the different friends Mai, Jan, Achim and Melinda don't give up and they even get reinforcements: this time Rina is also along for the ride. The search begins at Rina's home and leads into the mountains. Will you manage to rescue Tofu together with the Unstoppables?