of the ship with a crystal prism, informing them that Enterprise has been encased in an impenetrable force field. Kirk and Spock are then led back to the dungeon. After a while McCoy appears, in a trance, and leads Kirk back to Sylvia. Sylvia wants to experience human sensations, and appears in various feminine forms to stimulate Kirk's interest. Kirk plays along as he tries to get information. Sylvia tells Kirk that she and Korob are explorers from another galaxy, who wield their power through a device called a transmuter, which gives them control over matter. Sylvia then realizes Kirk is using her, and angrily sends him back to the dungeon. Korob comes to free Kirk and Spock, telling them that he has released their ship, and urges them to leave immediately, as he can no longer keep Sylvia under control. Sylvia, in the form of a giant cat, attacks him. Korob releases his scepter and Kirk picks it up, guessing it to be the transmuter. Kirk tells Sylvia that he has the transmuter. He destroys it when she threatens him with a phaser. The castle disappears and Sulu, Scotty, and McCoy return to normal. Looking down, Kirk sees two tiny blue and yellow creatures, apparently Korob's and Sylvia's true forms. Unable to survive without the transmuter, the two creatures die and disintegrate. Production Bloch wrote this episode, basing it on a short story of his, "Broomstick Ride" (1957) and also wrote the Star Trek episode, "What Are Little Girls Made Of?" Both mention the "Old Ones". The character of Asst. Chief Engineer DeSalle previously appeared in the episodes, "The Squire of Gothos" and "This Side of Paradise" wearing a gold command shirt. Reception Critical response In 2017, H&I included "Catspaw" in a list of "eerie, disturbing and downright scary" episodes of the series. The list noted that the episode was written by Robert Bloch, writer of the famous psychological thriller Psycho. In 2020, Den of Geek ranked "Catspaw" as the 28th most scary episode of all Star Trek franchise television episodes, including later television series. In 2021, ScreenRant ranked "Catspaw" the 10th scariest episode of all Star Trek franchise television episodes, including later series. Release Catspaw was released on VHS on April 15, 1994, by CBS Paramount International Television. See also The Monkey and the Cat, the source of the idiom "catspaw" References Citations Sources External links "Catspaw" Side-by-side