Land of the Giants

After some encounters with giants, the Earthlings stumble upon a ticking clock with a radium dial. Mark thinks they can pillage the clock for repair parts and fuel. Unfortunately, two giant scientists are testing a sound detector.

After getting only a small amount of radium, the Earthlings are forced to abandon the clock. Valerie and Betty get captured, and one of the giants interrogate them. The remainder of the group are force to choose between abandoning the two women, or using one of the ship's fuel cells to blow up the sound detector and create a diversion.

The group decides to sacrifice the fuel cell (over Fitzhugh's complaints). Dan and Steve free the girls, but Mark is injured planting the explosive. Reluctantly, Fitzhugh comes to the rescue and, overcoming his qualms, blows up the fuel cell, allowing the rest to escape. Back at the camp, the group acknowledges Fitzhugh's efforts with a medal for heroism.