The sensational celebrity of Circus Europe is so-called Tarzan (Rudolf Hrusínský) - half-monkey and half-human. One of the circus visitors, anthropologist Forejt Vlastimil Hasek, is intensely interested in the weird creature. He meets a young attractive woman named Regina Smith (Jana Stepánková), who introduces herself as Tarzan's fiancé. Tarzan, however, is in fact German Baron Wolfgang von Hoppe, whose father left for Africa with his wife and a very little Wolfgang in 1904. Soon afterwards, the news about their death arrived. The vast family property is now managed by nephew Heinrich (Martin Ruzek). After thirty years, Wolfgang was discovered as a wild forest savage living with apes. He was recognized and taken back to Europe.