A scientific expedition searching for fossils along the Amazon River discover a prehistoric Gill-Man in the legendary Black Lagoon. The explorers capture the mysterious creature, but it breaks free. The Gill-Man returns to kidnap the lovely Kay, fiancée of one of the expedition, with whom it has fallen in love.

As a Civil War veteran spends years searching for a young niece captured by Indians, his motivation becomes increasingly questionable.

Spain, 1518: young caballero Pedro De Vargas offends his sadistic neighbor De Silva, who just happens to be an officer of the Inquisition. Forced to flee, Pedro, friend Juan Garcia, and adoring servant girl Catana join Cortez’ first expedition to Mexico. Arriving in the rich new land, Cortez decides to switch from exploration to conquest…with only 500 men. Embroiled in continuous adventures and a romantic interlude, Pedro almost forgets he has a deadly enemy…