Brain Guy (also known as Observer) is a hyper-intelligent and psychic alien from the Observer homeworld. He served as one of the Mads alongside Professor Bobo and under the leadership of Pearl Forrester.

He is portrayed by Bill Corbett and was a regular character from Seasons 8 through 10.


The Observer who would come to be known as "Brain Guy" hails from a planet populated by aliens who claim to be without bodies (despite obvious evidence to the contrary) and carry their bright-blue brains in large Petri dishes, rather than inside their (supposedly nonexistent) skulls. They utilize their mental powers to operate as a hive mind and "observe" the behavior of inferior beings.

He first contacts our heroes following the destruction of Earth, when Mike and the Bots find themselves orbiting the Observer homeworld, where Pearl and Bobo have landed and are being observed. Tests on the SoL crew indicate that he is less intelligent than Tom Servo and he is briefly deposed by Tom. When Mike orchestrates the destruction of the Observer homeworld, he escapes the destruction along with Pearl, becoming the newest "Mad".

With "The Mads"[]


Like his colleagues, Professor Bobo, (Kevin Murphy), and Pearl Forrester (Mary Jo Pehl), Brain Guy is deeply dysfunctional. Unlike Bobo and Pearl, Brain Guy apparently has a considerable social and sexual life once the SoL and the Mads return to Earth.

Observer occasionally claims that he does not actually have a physical body, and that what other see is only a physical manifestation of psychic energy. This claim is inconsistent, though, as he is shown to have some of the weaknesses that come with a physical body, such as vulnerability to pain and (as Professor Bobo put it) "B.O." Observer denies this, although eventually he gives himself a sniff and admits that he does, in fact, "reek". Observer also claims to not have a soul.

Exposure to Pearl's autocratic manner also appears to degrade Observer's powers over the course of their time together. Despite this, Observer displays a fondness for Pearl and Bobo (and even Mike on occasion). When his former compatriots return, Observer ultimately decides to stay on Earth with his new friends rather than return to his reconstituted homeworld. Despite his apparent weakness, Observer is able to restrain his former compatriots until they can be separated from their brains with the help of Pearl and Bobo, at which time Observer re-creates them as simple-minded residents of Wisconsin.

Pearl's playful dousing of his brain in Mountain Dew temporarily interferes with Brain Guy's abilities, allowing the Satellite of Love to crash to Earth. After the experiment ends, he leaves to take a job as the supreme intelligence on the planet Reilos 14, which both he and Pearl seem to find demeaning.

Brain Guy's new position appears to have been temporary, as he is seen to be traveling with Pearl and Bobo in The Widowmaker when they communicate with Moon 13. They stop briefly to interact with Kinga and Max and observe the progress of their experiment.

Brain Guy attends Kinga's aborted wedding to Jonah Heston, which is also attended by other members of the Observer Hive Mind. There does not seem to be any animosity between Observer and his people.

Observer does not join Pearl when she moves into Moon 1. His current status is unknown.

Powers and abilities[]

Brain Guy claims, like his fellow Observers, to be omniscient and omnipotent, much like Q (and his people from Star Trek), but frequently fails to demonstrate these supposed abilities. Observers claim to have a degree of mental telepathy (mind-reading) but this ability seems to be weak and inconsistent. Observer (and his people) do not seem to be pre-cognizant.

He has the ability to transport items and living beings through space and time and, upon joining the "Mads", usually ends up being the one who sends the movies to The Satellite of Love via his mental abilities. He can also manifest previously non-existent objects at will. This power was limited, though, as he stated he was "not THAT omnipotent" when Pearl complained that he did not re-locate Castle Forrester with his mind (in Experiment #1011 - Horrors of Spider Island).

As seen when he is imprisoned in Rome, he is dependent on the proximity to his brain to maintain both his full intelligence and mental powers.


Pearl Forrester[]

Observer was deferential to Pearl, most likely out of gratitude for her saving him from his planet's destruction. He assisted her in her tormenting of Mike (and often of Bobo), and was generally a willing participant in her schemes. Observer was less hesitant to contradict or disobey Pearl than Bobo was, but he was often cowed by Pearl's overbearing personality.

Professor Bobo[]

Observer had a complicated relationship with Professor Bobo. Initially, Observer considered Bobo a lesser being and scorned him. They eventually bonded over their shared mistreatment at the hands of Pearl, and formed a rough alliance. This bond strengthened over time, though they could still be competitive (such as at dancing or arm wrestling). The pair would occasionally conspire to frustrate Pearl, though they could make it seem unintentional (or, at least, not malicious). Despite this, Observer was still inclined to demean or harm Bobo at Pearl's behest.

Mike Nelson[]

Observer held a grudge against Mike for the destruction of his homeworld and willingly joined in Pearl's experiment to torment Mike. Observer testified against Mike at his galactic trial, lying during his testimony to make Mike seem more evil. Like his relationship with Bobo, Observer's attitude towards Mike softened with time, and they enjoyed some male bonding when Pearl and Mike switched places during Experiment #913 - Quest of the Delta Knights.


  • Though Observer is consistently referred to and addressed as "Brain Guy" by the other characters, he is always identified as "Observer" in the show credits.

The Mads
Principal Dr. Clayton ForresterDr. Laurence ErhardtTV's FrankPearl ForresterProfessor BoboBrain GuyKinga ForresterMax
Secondary Gerry and SylviaDr. PeanutThe ObserversSynthia ForresterArdySkeleton CrewDr. Donna St. PhibesBonesyMega-SynthiaDr. KabahlM. WaverlyGrowler
Mirror Universe Mike NelsonCrow T. RobotTom ServoGypsy
Locations Gizmonic InstituteDeep 13Deep ApeThe WidowmakerObserver homeworldCamping PlanetAncient RomeCastle ForresterMoon 13Moon 1Deep Hurting

The Satellite of Love
Primary Residents Joel RobinsonMike NelsonJonah HestonCrow T. RobotGypsyCambotTom Servo
Minor/Other Residents BeeperMagic VoiceXT-5000TimmyMike's RobotClayton Forrester (mirror)TV's Frank (mirror)Eddie Nelson (alternate universe)The NanitesMike Nelson (robot)WinstonM. WaverlyMatt Claude Van DammeGrowlerEmily Connor
Visitors EnochDemon DogsNuveenaGypsy (mirror)Tom Servo (mirror)MonadThe ObserversFinneganHadrianAdrienne BarbeauLydiaOrtegaPhantom of KrankorHenry KissingerBowler-Hatted GuyDelivery ManGoosioMikey the Mike spriteMikesocksy the Mike's Socks SpriteBrain GuyPearl ForresterProfessor Bobo
Terminology AirlockDeus ex MachinaHexfield ViewscreenHyper-warp escape shipsJet ScreenManipulator armsMovie signRocket Number 9The TubeUmbilicusWhirlpool
Locations BridgeCrow's RoomJoel's roomKitchenMike's roomMystery Science TheaterTheater hallwayTom's room