The first in Terry Pratchett's series of three books about Johnny Maxwell. I accidentally read Johnny and the Bomb (the third book) first. This book finds Johnny playing a video game called "Only You Can Save Mankind," but in his case it gets a bit more personal: the aliens request a truce and ask him to protect them from the other players (this is NOT how the game is supposed to go). And then he starts waking up in the cockpit of his ship, flying with the aliens. As he leads the aliens away from game space, the game company finds itself in trouble because players can't find any enemies to fight, and Johnny's sleep gets steadily poorer.
I thought Johnny and the Bomb was the better book ... and I didn't think much of it. I like Johnny and his friends, but not enough. I don't think I'll be reading the middle book in the series.