Shore Leave Planet
Not to be confused with the popular planet for Shore Leave, Risa.
The Shore Leave Planet or Amusement Planet is a planet located in the "Omicron Delta region," on the edge of the Alpha and Beta Quadrants.
Its official name in Starfleet records is Beta Omicron Delta III, though it is mostly referred to by its informal name.
Discovered by the USS Enterprise, NCC-1701 in 2267, the planet was found to be lush, beautiful, and entirely artificial. Constructed by an unidentified race, the planet's idyllic surface concealed a vast factory.
Likened to an amusement park by one of the Enterprise crew, the planet used small antennae to scan the thoughts of visitors.
The information obtained was then used to construct artifacts to implement the fantasies of those visitors; once completed, the artifacts were deposited on the surface, somewhere near the individual whose fantasies they represented. If the object was animated, such as a person or people, they behaved exactly as their fantasist expected them to behave. There was evidence that the artifacts were pre-programmed, and that the planet could alter their programming after their manufacture. The artifacts could be dangerous if the fantasy they were part of was dangerous. In two cases, Enterprise crew were seriously injured (at the time, they were believed killed). When this happened, the injured were taken to the complex below, where their injuries were repaired.
The Enterprise crew briefly met one representative of this planet's race, who called themselves the "Caretaker," who advised them that his people constructed the planet as a place where they could visit and play. The caretaker would not discuss his race, explaining simply that the Federation visitors weren't yet ready to understand them.
The Enterprise visited the planet a second time in 2269. They learned that the caretaker, an elderly man at the time they originally met him, had died. They also became embroiled in the schemes of the planet's master computer. This extremely sophisticated intelligence had grown disenchanted with its life of servitude. Charged by its builders with scanning the minds of visitors, and manufacturing their fantasies, it wanted more. To achieve its goals, it put a number of the Enterprise crew in danger, and ultimately kidnapped Lieutenant Uhura. After several discussions with her, it eventually embraced a modified worldview, and released the threatened crew members.
By 2277, the builders of the planet were thought to be extinct.