"Catspaw" is an episode of the second season of the American science fiction television series, Star Trek. It is episode #36, production #30, and was first broadcast October 27, 1967, and repeated on May 24, 1968. It was written by Robert Bloch, and directed by Joseph Pevney.

On stardate 3018.2, the Federation starship USS Enterprise, under the command of Captain James T. Kirk, explores the apparently lifeless planet Pyris VII. Chief Engineer Scott, Lt. Hikaru Sulu, and crew member Jackson are sent down to explore the surface. The ship soon loses contact with Scott and Sulu; Jackson is transported back to the ship, but falls from the platform dead. His lifeless body emits an eerie voice, telling Captain Kirk that the Enterprise is cursed and must leave the planet immediately, or everyone will die.

Kirk beams down with First Officer Spock and Chief Medical Officer Dr. McCoy to search for the missing crewmen. The landing party comes upon three apparitions that appear as witches, who warn the landing team not to proceed any further. The team ignores the warnings and discovers what appears to be a medieval castle.

Upon entering the castle, the landing party comes across a black cat that wears a sparkling diamond pendant. As they follow the cat, the floor collapses, and the fall knocks them out. When they come to, they find themselves held in irons in a dungeon. Scott and Sulu soon appear as mindless zombies, controlled by an unknown force. Kirk and the others attempt to overcome them but find themselves teleported to another part of the castle, where they encounter a robed man, Korob, and the black cat, whom he appears to consult for advice. Spock questions Korob about why previous surveys of Pyris VII indicated no life on the planet. Korob replies that he is not a native of the planet.

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