Purchased Person

As with all Earth’s exported criminals, his body and will belonged to the race that had bought him, but the thoughts of the brain inside were still his own. Far off at the core of some gas-giant planet or floating in space, a creature with a wholly different physical structure was using this man’s eyes and limbs as his own, linked by tachyon transmission to the monitor units implanted in each Purchased Person’s skull. But inside that skull the original mind was spending a lifetime in solitary confinement.

Frederik Pohl and Jack Williamson