Overview
Tom Servo is a red puppet that has a gumball machine (Carousel Executive Snack Dispenser) for a head, a body composed of a toy "Money Lover Barrel" coin bank and a toy car engine block, and a bowl-shaped hovercraft skirt (a Halloween 'Boo Bowl') instead of legs. His arms are a pair of small white ventriloquist's dummy hands on the ends of springs that are not really functional as arms, a point that is commented on occasionally throughout the series. Some episodes feature Tom with objects already in his hands, raising the unanswered question of how they got there. His shoulders are made from the front of an Eveready Floating Lantern. Because Servo's head is transparent, chromakeyed images appear projected through it, and thus a second puppet was built for use in the theater segments, entirely spray-painted black. This black Servo also appeared in a host segment in episode #609: The Skydivers.
Servo's appearance has changed over time. In the pilot for MST3K, the robot who would become Servo was named "Beeper," who just spoke in beeps that only Crow could understand. He was an all-silver robot vaguely shaped like the ultimate Servo, with funnel-shaped shoulders, silver rubber tube arms, and a small fishbowl for a head. He was renamed 'Servo' after a vending machine called the Servotron. Sometime between the pilot and episode #K03: Star Force: Fugitive Alien II Servo's head was replaced with the now-familiar gumball machine for most of the series. (MST3K archival site mst3ktemple.com presents a substantive argument that this replacement was probably done before or during episode #K01: Invaders from the Deep, based on an analysis of related set and costume changes.).
In Season 1 on the Comedy Channel, he was given a red color, longer black tube arms, squared white shoulders, a different hoverskirt, and the Carousel Snack Dispenser gumball machine head with a white beak. Around episode 105: The Corpse Vanishes, Servo's head was replaced with a slightly modified version of his "Carousel" head. The "neck" was slightly wider and the beak (now silver at this point) appeared smaller. This version of Servo's head would be used for the remainder of Season 1. For Season 2, the black tubing used for his arms was replaced by a pair of small silver springs and the more familiar Carousel Dispenser head design (KTMA/pre episode 105) returned with a silver beak. This physical form was pretty much the same throughout the remainder of the series, save for a brief flirtation (during episodes #205: Rocket Attack USA and #206: Ring of Terror) with a slim cylindrical gumball-machine head to try to reduce the screen area Servo's head obscured. It was introduced as a "haircut" that Joel gave Servo, but was quickly abandoned. By mid season 3 an extra cap from another Carousel Dispenser was added just below the "bubble" making Tom's head appear slightly taller and slimmer. Briefly in early season 4, Servo's white hands were changed to beige before returning to white after only a few episodes. During a host segment in the Sci-Fi era, he briefly acquired the body of a "beautiful butterfly."
Servo's voice and personality also changed during the show's early years. While Josh Weinstein operated Servo during the KTMA season, Servo spoke rather slowly with a squeaky voice, and was somewhat immobile during host segments but oddly very active in the theater. In episode K06, Weinstein switched to a lower voice that Servo repeatedly proclaimed as his new "MIGHTY VOICE!" When Weinstein left at the end of Season 1, Kevin Murphy took over Servo's operation and tried to match Weinstein's Servo voice and personality, but gradually developed a somewhat new Servo sound and character (though Murphy has a fairly deep voice himself). This was explained as tinkering by Joel. During Murphy's tenure, Servo took many opportunities to showcase his excellent singing. He also has an extensive underwear collection (as seen in Mystery Science Theater 3000: The Movie), as well as a large number of duplicates of himself that he made in episode #420: The Human Duplicators (also seen in episode #1004: Future War, and episode #1013: Diabolik).
Whenever a member of the cast is required to dress in drag for a sketch, Servo usually does the honors. This is both because of the dichotomy of women's clothes amusingly contrasted with puppeteer Murphy's strong baritone voice and because, in Murphy's words, "Servo looks better in a dress than Crow." Also, Servo is the only robot (other than Cambot in seasons 5-10) whose entire body can seen on the show, since Crow's legs are behind the desk and Gypsy's body is several yards long.
Servo normally has a condescending personality and at times can make literary and technical references that are above his companion's heads. He frequently attempts to seem physically imposing to others, once acquiring "lifts" for his hover skirt to increase his size (accused by Mike of suffering "short man's disease") and on another occasion showing off a small arsenal he had acquired while drifting through space. Almost invariably, however, any attempts at confronting danger or displaying his intellectual skill cause him such frustration that he ends up crying, often needing consolation from Joel or Mike.
Furthermore he's easily rattled by sarcastic remarks made from Crow, such as the time when he made fun of his infatuation with a boy's pet turtle Tibby in the episode 'Gamera'.
He does have a good understanding and intellect in spite of his sensitivity and frustration, and has revealed in the episode 'The Gunslinger' that he's able to teleport at will, even though he only demonstrates this on rare other occasions.
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