 Which relationship best describes the dynamic between the prisoners and the figures controlling them?
This was so with all of their foods, with their cigarettes, with everything in their prison—or their cage. He had felt the inner tug of command, said good-by to the women and returned to his smaller compound within its own barrier dome. Then came the invisible aura of strain in the air, the shimmering illusion of heat that was not heat, that was prelude to his teleportation ... if that were the word. As in all of this strange universe, excepting the dome-cages in which the captives were held, the training hall followed no rules of three-dimensional space. The opposite wall resembled a diagonal cross-section of an asymmetrical dumbbell—that was the closest Tennant could come to it in words.
 The prisoners serve as entertainment for the figures, who seem to have made a game out of snatching up humans and manipulating their thoughts and behaviors.
 The prisoners are being groomed to serve as future collaborators in an intergalactic sex trafficking stint, carried out through the fourth dimension.  The prisoners serve as entertainment for the figures, who seem to have made a game out of snatching up humans and manipulating their thoughts and behaviors.  The prisoners have committed some sort of Earthly crime, and their punishment -- in order to avoid the death penalty -- is to spend a sentence in a labor camp operated by the figures.  The prisoners have volunteered to be part of the figures' experiment for a specific time period, under the agreement that they will be returned to Earth in the condition they left it.