Andromeda Gun - G7, emmisary of an alien race of energy-beings, is sent to Earth to explore for energy sources his race needs. But when G-7 takes over the body of Johnny McCloud something happens - instead of exercising total control, G-7 is changed, involved in McCloud's personality and emotions. And Johnny McCloud, the amoral gunfighter, is changed too. Here is the story of a strange symbiosis of man and alien, and the crucial events upon which the future history of Earth depends. Johnny McCloud/G-7, the symbiote, can change Earth's history. This is the weakest of the pair in terms of plausibility, but it still has moments of Boyd's irreverent creative touch.