Maik Klingenberg is a fourteen-year-old boy left to spend his summer vacation alone at his family's villa, as his mother is in rehab and his father is away on a business trip with his assistant. Everything changes when Tschick, whose real name is Andrej Tschichatschow, arrives. Tschick, from the high-rise apartments in Hellersdorf, has somehow made it from a special education school to a gymnasium, and brings along a stolen car.

Thus begins an adventurous journey without a map or compass through the sun-drenched German provinces, reminiscent of the river journey of Tom Sawyer and Huck Finn. They head towards the vast world, with their destination randomly set to Wallachia, where Tschick's uncle supposedly lives.