A runaway asteroid is heading to Earth. Strong and Dale join the Polaris to destroy it. Manning, left in command while the others sleep, recklessly increases speed to save the Earth and be a hero. Can the tubes handle the strain?
As the asteroid hurl towards Earth, Polaris is dead in space with a damaged tube. Capt. Strong takes Corbett and Manning outside the ship to replace the tube. But where is the runaway asteroid?