A chance discovery leads American mining engineer Ben Harris and acquaintance Harold to discover a lost city under the sea while searching for their kidnapped friend Jill. Held captive in the underwater city by the tyrannical Captain (Vincent Price), and his crew of former smugglers, the three plot to escape...
When Chester accidentally memorizes and destroys the only copy of a secret Russian formula for a new and improved rocket fuel, they are thrust into international intrigue, trying to stay alive while keeping the formula out of enemy hands.
