A4D Wiki
Dexter's Laboratory
Genre Comic science fiction
Opening theme "Dexter's Laboratory"
(main title)
Ending theme "Dexter's Laboratory"
(end title)
performed by Mako and Agostino Castagnola
Country of origin United States
No. of seasons 4
No. of episodes 78 (221 segments)
Production company(s) Cartoon Network Studios
(1996–1997 as H-B's division; 2001–2003)
Hanna-Barbera Cartoons, Inc.
Distributor Cartoon Network
Warner Bros. Television
Original network Cartoon Network
Original release Apr 27, 1996 - Nov 20, 2003
What a Cartoon!

This is a list of characters who appeared on the American animated television series Dexter's Laboratory, which aired on Cartoon Network.

Main characters


Dexter (voiced by Christine Cavanaugh in seasons one and two, and Candi Milo in seasons three and four) is a young genius who has a secret laboratory and speaks with an accent of unknown origin. His intelligence makes him the brains of the family and he is one of the world's greatest inventors, having created countless weird and amazing machines and experiments. He is always working on new inventions and creations every day, but his sister Dee Dee is always breaking into his lab and destroying his work. Despite his geniuses, Dexter is in fact very naive and occasionally ignorant about common outside subjects. The daily events surrounding Dexter's life mainly revolve around his relationship with his sister and everything that happens between the two.

Dee Dee

Dee Dee (voiced by Allison Moore (Season 1 & 3), Kathryn Cressida (Season 2 & 4) is Dexter's older sister, who is mostly seen destroying or ruining Dexter's lab in various ways. The daily events surrounding Dee Dee's life mainly revolve around her relationship with her brother and everything that happens between the two. Though she was shown to get hypocritically angry when she found that Dexter had been in her room and messed with her stuff. Dee Dee also loves ballet, puppies, unicorns, playing dolls with her friends, messing around in Dexter's laboratory and generally depicts all the stereotypes concerning normal girl activities. Dee Dee has a great love and fascination for buttons to the point that her catch-phrase is "Oooooooh, what does this button do?". She rarely wears her full length of hair down except on rare occasions, mostly when sleeping, preferring to keep them in their recognizable style.


Mom (voiced by Kath Soucie) is Dexter and Dee Dee's red-haired mother. She is an everyday house mom as well as a Germ-o-phobe. She usually wears a pair of yellow rubber gloves, and is mostly seen keeping things clean around the house. She is a very busy mom who is seen doing lots of other work around the house as well.


Dad (voiced by Jeff Bennett) is Dexter and Dee Dee's blonde father. He loves bowling, golf, fishing, and has an unnatural affinity for his wife's muffins, of which she can expertly create (according to him, the muffins are the reason he married Mom, though this may have been a spur-of-the-moment remark, since he desperately wanted the muffins at the time).

Mandark Astronomonov

Susan "Mandark" Astronomonov (voiced by Eddie Deezen) is the main antagonist. He is Dexter's rival and later mortal nemesis who often seeks to destroy both Dexter and his lab to prove once and for all that he is the superior genius. He has a major crush on Dee Dee despite her having no interest in him. His hippie parents Windbear and Oceanbird named him Susan because they thought he was a girl because of his long hair that they never cut, so Susan cut his hair into the bowl style with an "M" that he wears today and renamed himself. Mandark also has a sister named Olga Astronomonov (a.k.a. Lalavava).

Secondary characters

  • Mee Mee (voiced by Kath Soucie in her initial appearances, and Kimberly Brooks in later appearances) and Lee Lee (voiced by Kath Soucie) are Dee Dee's best friends. They like the same things as Dee Dee and often cause havoc in Dexter's lab or play with the Pony Puff Princesses that they love so much.
  • Quadraplex T-3000 Computer (voiced by Kath Soucie) is Dexter's computer that oversees the running of the lab and has a personality of its own.
  • Zeke The Dog (voiced by Frank Welker) is a recurring minor character on the show who usually just fills the role of the family pet. Although usually portrayed as a minor character with little role in the series, he did play a major part in the episode Fantastic Boyage (this was the only episode in which any major focus was put on him).
  • Koosalagoopagoop (voiced by Dom DeLuise) is Dee Dee's imaginary friend who is a rainbow dragon from an imaginary world called Koosland. Dee Dee is always going into her room to go and visit him in his imaginary world which she enters via a portal of pink hearts and magic that Koosy can open up or can be accessed from the heart marking on his stomach.
  • Douglas E. Mordecai III (voiced by Tom Kenny) is one of Dexter's best friends. He attends school with Dexter and is similarly geeky.
  • Action Hank (voiced by: Michael Armstrong ("Beard to be Feared"), John Garry ("Decode of Honor"), and Kevin Michael Richardson ("911") is a heroic crime fighter and a television action hero. He is essentially a parody of several popular action shows/movies or action stars from the 70's and 80's, all rolled up into one. These include: Chuck Norris, Mr. T, G.I. Joe, John Shaft and John Rambo. Along with Major Glory and Albert Einstein, he is idolized by Dexter.
  • Phillips Luzinsky (voiced by Frank Welker) is Dexter's elementary school teacher at Huber Elementary and the most common teacher seen in the series.
  • Monkey (voiced by Frank Welker) is Dexter's lab monkey, who secretly has superpowers, unbeknownst to Dexter, and often tries to give him powers via unusual experimentation. Monkey is considered the planet's greatest Superhero. He stars in the back-up Dial M for Monkey cartoons, and occasionally appeared in several episodes of Dexter's Laboratory out of his superhero persona. Working for Global Security, Monkey protects the world from intergalactic villains, large monsters, and natural disasters. He also has his own nemesis (who is a female duckling) called Quackor, who is owned by Dexter's nemesis, Mandark.
  • Agent Honeydew (voiced by Kath Soucie) is Monkey's sidekick and girlfriend, who can ask Monkey for help with her telepathic abilities.
  • Commander Chief (voiced by Robert Ridgely (Season 1), Earl Boen (Season 2) is the head of Global Security whose main duty is to monitor the Earth for any signs of danger. He works closely with Agent Honeydew, Monkey, and The Justice Friends. He is only ever shown from the waist up in a TV monitor and it is hinted that he is actually trapped in the monitor. He is a parody of Marvel Comics' Nick Fury.
  • Major Glory (voiced by Rob Paulsen) is Dexter's favorite superhero, and the leader of the Justice Friends. He is a parody of Marvel Comics' Captain America.
  • Valhallen (voiced by Tom Kenny) is the self-described "Viking God of Rock" and a member of the superhero team The Justice Friends. His name is a combination of the famous hard rock band Van Halen and the Nordic Heaven, Valhalla. Valhallen is a parody of the Marvel Comics' version of Norse god Thor but with several traits referencing those of He-Man from He-Man and the Masters of the Universe.
  • The Infraggable Krunk, or sometimes referred to as Krunk (voiced by Frank Welker) is a member of The Justice Friends. He is the biggest and strongest Justice Friend, but he is also the dumbest and kindest. He is a parody of Marvel Comics' The Incredible Hulk.
  • Mitch and Clem, (voiced by: Rob Paulsen and Tom Kenny) are puppets seen in a TV show during the Justice Friends segments. They also appear in short live-action time-filler segments of their own. Their appearances parody 2 of the Muppets, Bert and Ernie, from Sesame Street and they also perform behind a Sesame Street-like wall. Their main sketch is Mitch bonking Clem on the head, which is most likely a reference to classic puppets Punch and Judy. In one episode they are controlled by Major Glory and Valhallen and vice versa in Krunk's dream. They also made an appearance in The Powerpuff Girls episode, "Mommy Fearest".