Hajo wants to become a sailor despite his mother's fears and his father's death at sea. He befriends the son of a captain of the Dutch East India Company and joins the crew of their ship bound for the East Indies. Hajo's simple-minded friend Padde comes along by accident. Together they live through many of the dangers to which sailors were exposed in the 17th century. They survive a shipwreck and escape from an attack by natives that separates them from the rest of the crew. With help from a pretty Oriental girl they must find their way to safety. However, their friendship is threatened when the boys all fall in love with Dolimah.