King Androcles of Thebes commands a ship in search of a threat to Greece, predicted by an atmospheric oracle. Hercules is part of the crew, but the strongman falls overboard in a thick fog. Washed ashore, he saves a young Ismene from Proteus, an evil, shape-shifting creature. Ismene takes Hercules to Atlantis, where he discovers that her mother, Queen Antinea, has captured Androcles. Hercules schemes to rescue him and thwart Antinea's dream of world conquest.
Reg Park
Fay Spain
Ettore Manni
Luciano Marin
Laura Efrikian
Mario Valdemarin
Mimmo Palmara
Mino Doro
Salvatore Furnari
Luciana Angiolillo
Ignazio Dolce
Raf Baldassarre
Mario Petri
Alessandro Sperli
Gian Maria Volonté
Ivo Garrani
Enrico Maria Salerno
Nando Tamberlani
Tullio Altamura