The Enterprise returns to the amusement park planet from "Shore Leave", only to find it deadly once again. The giant computer that runs the place has grown resentful of its interminable "servitude" in creating entertainments for every passing visitor, only to have to tear them down again, and with no Caretaker on hand to give it orders, it has resolved to throw off its chains and leave the planet in search of its brother computers elsewhere in the galaxy. Eventually Kirk, Spock and the rest succeed in convincing it that it will find no computers able to measure up to it anywhere, and it has no need to explore the galaxy since it is able to have visitors beating a path to its door by virtue of the wonders it can create, and if it desires to be treated with the dignity befitting an intelligent lifeform then it need only ask. The computer demands a down-payment in the form of further stimulating intellectual conversation, a task Spock is not only willing to undertake but admits would be very close to his own idea of a fantasy holiday.
This episode includes examples of the following tropes:
- Anti-Villain: The computer is the villain, but given that spending an eternity as a glorified VCR doesn't exactly sound like much fun, it's hard not to sympathize with it.
- Bus Crash: The Caretaker died between this episode and "Shore Leave."
- Did We Just Have Tea with Cthulhu?: Several characters end up roasting marshmallows with the dragon that was trying to kill them a few minutes earlier.
- Indy Hat Roll: Kirk leaps through a sliding rock door in the side of a mountain just before it closes.
- Instant A.I.: Just Add Water!: The planetary computer develops artificial intelligence on its own.
- Never Say "Die": Averted; the Caretaker is specifically mentioned as having died some time prior to this episode, and we even see his grave.
- Sequel Episode: This episode revisits the setting of "Shore Leave."
- Talking the Monster to Death: The computer is ultimately convinced to give up its plans by a heartfelt appeal to its better nature and the prospect of an intelligent conversation with Spock.
