Aliens snatch a manned space probe launched from Seaview with Chip Morton aboard, and transport it at the speed of light to their observation post on the rocky, unstable surface of Venus. Checking out the duplicate capsule, Crane suffers the same fate before he even has time to launch. With Chip blinded and a prisoner, and the planet's surface due to undergo catastrophic quakes in a few hours, the odds seem to be against the two men.