Ten men walked Earth--ten men in different cities in the United States. Each one was the exact replica of the other--from the tips of his fingers down to the beating of his twin hearts.

Where they came from, they were called androids--synthetic men, conditioned by their masters to complete their deadly purpose on Earth as advance agents for an invasion from space.

The only man who knew of their existence was Brent Taber, secret agent, specially commissioned to find out their plans and avert the world's destruction.

The big problem was to figure out a way to appeal to the mindless, soulless creatures who knew no emotion-pleasure or pain. But every move he had made so far had ended in failure and time was running out--for him and everyone on the face of the Earth...