Guest stars:

John Ruskin             Galt, master Thrall of the Planet Triskelion
Angelique Pettyjohn     Shana, Kirk's drill Thrall
Steve Sandor            Lars, Uhura's drill Thrall
James Ross              Tamoon, Chekov's drill Thrall
Victoria George         Jana,?
Mickey Horton           Kloog, Large hairy creature perhaps from Hansens planet mentioned in Galileo 7.
The Providers     Incorporial life forms with only the brain remaining, inhabitants of Triskelion who capture beings from other worlds to participate as breeding stock for arena type games for their pleasure.

Crew Appearances:
Kirk, Spock, Mccoy
Uhura
Chekov
NO Sulu
Ensign Haynes, science station and navigation
James Doohan as a voice of one of the 'Providers'
 
Kirk, Chekov and Uhura are spacenapped by the beings of Triskelion, and forced to partake in gladiator games they have designed to amuse themselves. Kirk turns the tables by making a wager which will either provide many more participants in the "sport," or the aliens will have to free those already in slavery.

Theme: Slavery, bondage and freedom to choose

Gamma 2: uninhabited planet with automatic communications and an astrogation station.

Triskelion: a inhabited planet in a trinary sun system

Quatloos: system of money on Triskelion

M24 alpha: The system that Triskelion is in.

Quotes:
"What other use is there for Thralls?"
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