Directed by Karel Zeman | Starring: Vladimír Bejval, Petr Herrmann, Josef Lukáš, Zdeněk Husták

Most classical sci-fi from K. Zeman. Four young boys visit a dinosaur exhibit at the New York city Museum of Natural History. They then row out onto Central Park Lake where they find a secret cave and paddle into, and go back-in-time into a wondrous prehistoric world filled with the very dinosaurs they had just seen.