Arthur Wasson

The first manned flight to Mars returns after having been out of communications since it had arrived on Mars. What would it reveal?

Pat Garrett arrives in Abilene where he catches five of Butch Cassidy's gang. He calls in Wyatt Earp and Bat Masterson and they learn there is a half million dollar shipment of money arriving by train and Cassidy is amassing enough men to take it.

In 1973, the first manned expedition to Mars is marooned; by the time a rescue mission arrives, there is only one survivor: the leader, Col. Edward Carruthers, who appears to have murdered the others! According to Carruthers, an unknown life form killed his comrades during a sandstorm. But the skeptical rescuers little suspect that "it" has stowed away for the voyage back to Earth...