"The Apple" is episode No. 34, production No. 38, of the second season of the original science fiction television series Star Trek. Written by Max Ehrlich, and directed by Joseph Pevney, it was first broadcast on October 13, 1967 and repeated July 12, 1968.
In this episode, the crew of the Enterprise visits a mysterious paradisical planet controlled by a computer that is served by the local inhabitants.
On stardate 3715.3, the Federationstarship USS Enterprise arrives at Gamma Trianguli VI, a planet that appears to be a tropical paradise with very rich natural resources. Captain James T. Kirk leads a landing party including Chief Medical Officer Dr. McCoy, Ensign Chekov, First Officer Spock, Yeoman Martha Landon (Celeste Yarnall) along with other security personnel. They quickly find the paradise is extremely hostile; they lose security members to plants that shoot poisonous darts, explosive rocks composed of uraninite, hornblende, and quartz; soon, bizarre lightning storms follow. Transporting back to the ship is impossible as an energy field is drawing power from the Enterprise rendering the transporters inoperable.
Kirk orders the team towards a primitive village, carefully avoiding the planet's hazards. They find a native of the planet watching them from nearby bushes. The frightened native, Akuta (Keith Andes), says he is the chief of the people known as the "Feeders of Vaal". Small antennae on Akuta's head allow him to communicate with "Vaal", acting as the entity's eyes and ears for his people. During this, Chief Engineer Scott reports that the Enterprise is slowly being pulled towards the planet by a tractor beam. Kirk, suspicious of the "Vaal" entity, asks Akuta to take them to it. Akuta leads them to a rock formation that has a dragon-like head figure on one side. Spock's analysis shows that the entrance is protected by a force field, but appears to lead to an underground complex with a computer system, perhaps constructed by a long-dead civilization, which he believes is what is affecting the Enterprise. Akuta says that Vaal may wake to speak with them, but in the meantime, offers to show the crew his village.
The Enterprise crew find the villagers to be young and healthy, like Akuta, but lacking sophisticated knowledge. McCoy finds that they do not procreate, a practice forbidden by Vaal, but instead, a "replacement" is provided if needed. As they observe, they find that the villagers have a symbiotic relationship with Vaal; they provide Vaal with a supply of the explosive rocks from the planet, while Vaal appears to provide them with all other resources such as food and shelter. Spock and McCoy argue over the ethics of such practices, but Kirk reminds them they need to find a way to free the Enterprise.
During their time at the village, Chekov and Landon have begun flirting with each other, and go to a secluded area to kiss. When the natives see this, they try to emulate it; Vaal is instantly aware, and through Akuta, orders the natives to kill the strangers. One of the crew men is killed. The rest of the crew defend themselves including Landon who shows that the female members of the crew are also skilled in self-defence by using a combination of judo and karate to knock out two of her male attackers. Scott reports that the ship has only fifteen minutes of emergency power remaining which they are using fighting the tractor beam. Kirk orders his crew to prevent the villagers from feeding Vaal any more of the explosive rocks, believing them to be powering Vaal, and instructs Scott to fire the ship's phasers on the rock formation, hoping to drain Vaal's power before the Enterprise's. Vaal's power supply runs dry, and the force field collapses. The Enterprise is free of the tractor beam and returns to orbit for repairs. Engineering crews on the ship are ordered to prepare to investigate the Vaal computer systems, while Kirk tells a distraught Akuta that his people will now be able to experience normal life. Aboard the ship, Spock contemplates whether their actions were the equivalent of the apple of knowledge and driving the Feeders from their Garden of Eden.