内容简介：
In l970, George Adams lived in a suburb of Cincinnati, Ohio. A loner by nature, he suddenly realizes there is someone who looks and acts just like him, but this atwina is not of this earth. The alien who is reproducing himself to become George is one of thousands of microbes attached to the moon rocks brought to earth by the astronauts. As the rocks are displayed throughout the world the microbes are replicating anyone they can latch onto and replace. George and his co-worker, Shelia, outsmart their alien twins several times, eventually fleeing to Kentucky where they stumble onto the key to destroy the aliens.