Star Trek The Original Series S01 E15 – Shore Leave
Captain Kirk orders shore leave for the Enterprise crew on a seemingly uninhabited planet in the Omicron Delta system. The landing parties begin to see strange sights, such as a white rabbit a la Alice in Wonderland, Don Juan, and a sword-wielding Samauri. Also, Kirk sees (and fights) an image of Finnegan, a rival from his Starfleet Academy days. Spock discovers that the planet seems to be drawing a large amount of energy from the ship’s engines, placing the Enterprise in danger