Planets both within the Terran Commonwealth and under Star Watch control, and outside it, have made use of dueling machines for many years to settle tensions and private arguments peacefully. Men in disagreements can have their brains hooked in and conduct a virtual duel with the weapons and in the environments of their choosing -- with no ultimate harm to anyone. Suddenly Odal, a warrior from the Kerak empire, somehow manages to send the Acquatainian prime minister into an irreversible coma in the dueling machine. Odal actually kills others in the machine, and the inventor Albertus Leoh can't figure out what's wrong. Leoh and his young Star Watch liaison, Jr. Lt. Hector, will eventually face Odal in the dueling machine, while Kerak obviously gears up to attack Acquataine and then even the Terran Commonwealth. How can they be stopped? This 1969 novel grew out of a 1963 Bova short story, and though the romantic subplot is leaden and cliched, the main thriller plot holds up all right.
