A visionary doctor, Dr. Janos Rukh (Karloff) invents a telescope that can look far out into space — into Andromeda — and pick up rays of light that will show the Earth's past. Looking at the past on a television-like screen, a group of assembled doctors as well as Dr. Rukh see a large meteor hit the earth thousands of years ago. Rukh convinces the doctors to go on an expedition to find the meteor that appeared to land in Africa. While in Africa, Rukh finds the meteor but is exposed to strong radiation ("Radium X") from the rock. Dr. Benet (Lugosi) takes a piece of the stone back to Europe and uses the meteorite to heal people, including curing the blind. Rukh, suffering from the radiation, glows at night when not treated and is slowly losing his mind.
The film features music by film composer Franz Waxman.