Kirk, Uhura and Chekov are abducted to be gladiators for the amusement of disembodied rulers.
Kirk, Uhura and Chekov are beamed from the Enterprise to the planet Triskelion, where they are made to fight as slave gladiators for entertainment. The planet's rulers, the Providers, are bored gamblers who bet on the outcome. Kirk is paired with a thrall named Shahna, who is drawn to him.
The plot gives Kirk a chance to make a bet with the Providers for the freedom of his crew. Meanwhile Spock and Scotty must command the ship while searching for them. Fans remember the arena fights and the strange, bored rulers.