This is a list of characters from the animated Nickelodeon TV series Invader Zim. The recurring cast includes long-term Nickelodeon voice actors Richard Steven Horvitz and Rodger Bumpass, as well as actors from live-action television such as Kevin McDonald (Kids in the Hall) and John de Lancie (Star Trek: The Next Generation). The creator and writer of Invader Zim, Jhonen Vasquez, also voices parts in the show.
Main characters[]
| Image | Name | Voice actor | Description |
|---|---|---|---|
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Zim | Richard Steven Horvitz Billy West and Mark Hamill (pilot) Melissa Fahn (Smeet) Andrew Russell (SMITE) |
An arrogant, overzealous, but incompetent Irken alien who has been sent to earth as an "Invader" by The Almighty tallest purely to keep him occupied from their plans. |
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GIR | Rosearik Rikki Simons | Zim's robot companion who is constructed from scrap parts and given to Zim by the Almighty Tallest instead of a regular S.I.R. (Standard-issue Information Retrieval) unit. |
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Dib Membrane | Andy Berman | Zim's rival and a eccentric young boy who is obsessed with the paranormal. He is also an self-proclaimed "defender of Earth", he attends skool with Zim and is determined to stop him from conquering Earth or expose him as an alien, though almost nobody believes him. |
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Gaz Membrane | Melissa Fahn | The menacing younger sister of Dib Membrane. Who is known for her dark, violent and antisocial personality, and frequently expressed her disdain for the rest of the human race, seeming to care about only two things in the world: pizza and video games. |
Secondary characters[]
| Image | Name | Voice actor | Description |
|---|---|---|---|
  |
Almighty Tallest | Kevin McDonald (Purple) Wally Wingert (Red) |
The leaders of the Irken Empire, who made Zim move to earth just to keep him and away from the real Operation Impending Doom II. As the name suggests, they are the tallest known Irkens alive and they have virtually absolute power, besides the Control Brains. |
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Professor Membrane | Rodger Bumpass | The world's smartest man, host of the popular television show "Probing the Membrane of Science", inventor of SuperToast, and father of Dib and Gaz, Membrane's scientific abilities are offset by incredibly poor parenting. |
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Ms. Bitters | Lucille Bliss | The teacher for Dib and Zim's class. She is a tall, slender, aged woman that is very creepy in many ways. True to her name, she is devoid of any compassionate emotion and having a very demonic hatred for life. |
Recurring characters[]
Tak[]
- Voiced by: Olivia d'Abo
Tak is one of the seemingly rare female Irken invaders who has had many unfortunate encounters with Zim. One of them includes inadvertently trapping her in a building on Devastis (The Irken military training planet), therefore missing her chance to take the test to become one of the Irken Elite Soldiers (and an Invader). In the one episode that she is in (Tak: The Hideous New Girl), she tries to overtake Zim's position on Earth, but fails miserably in the end. Tak's holographic disguise (particularly the clothing) somewhat resembles Johnny from "Johnny the Homicidal Maniac", a comic by Vasquez
MiMi[]
MiMi is a SIR unit who was built for Tak on planet Dirt. Her disguise is also holographic, and is generated as a cat.
Piggy[]
Piggy is a rubber pig that belongs to GIR, and is thrown into the time machine in the episode "Bad, Bad Rubber Piggy." GIR:"Why my piggy,I loveded piggy,i loved yooohoooou!!"
Computer[]
- Voiced by: Jhonen Vasquez
Zim's computer is normally seen talking with Zim. He is scattered around the House and Base so Zim can talk to him whenever he needs to. The computer often doesn't know what some of Earth's organizations (like the FBI) do, so he guesses. This often results in completely wild explanations. For example, when Zim asks computer to explain the FBI, the computer guesses and says the FBI was founded by demons, flies, and fights with corn. The Computer also seems to display defects, similar to GIR, in both that he lacks information on Earth and will occasionally change his voice tone to a much more harsh version at usually completely unnecessary times and situations. But he can be the voice of reason to some of Zim scheme's that usually end up in flames.
Minimoose[]
- Voiced by: Jhonen Vasquez
Minimoose is the Irken empire's superweapon, but Zim doesn't know how to use him.
Minimoose is Zim's other sidekick. Zim has stated previously that Minimoose has been with him since the beginning.
Invader Skoodge[]
- Voiced by: Ted Raimi
Skoodge is a successful competent Irken Invader, assigned to planet Blorch, home of the slaughtering rat people, due to his shortness. However, he was the first Invader to successfully conquer a planet in Operation Impending Doom II, but is prejudiced against by the Almighty Tallest, who proceed to launch him into the planet as the first shot of the destruction, but he survived. Skoodge's personality is kind and very loyal to The Almighty Tallest no matter how much they hate him. He was planned to be included in future episodes of the show, but it was canceled before the episode could be finished.
Sizz-Lor[]
An Irken character who works at Foodcourtia in an episode. Sizz Lor comes to Earth in the episode "The Frycook What Came from All That Space". It is his only appearance.
Minor characters[]
Keef[]
- Voiced by: Danny Cooksey
Keef is an annoying child that attends the Skool with Zim, and his only important role was in the second episode, "Bestest Friends". In this episode Zim got rid of him by removing his eyes and putting in new, robotic ones. He then tricked Keef into thinking the first thing he saw was Zim. The first thing Keef saw was a squirrel. He was supposed to appear in an episode they made called the "Return of Keef" but the animation was never finished because the show had been canceled.
Robo parents and gnomes[]
Robo parents and gnomes are Zim's helpers that guard him and help make him look more human. The Robo Parents appear to be poorly built and seem to have a lack of normal parental behavior. The Robo parents constantly go insane and attack visitors to Zim's house. The gnomes protect Zim's house at times when people are in the yard, such as Dib.
Bee[]
The creature who wrecked Zim's Voot Cruiser in an episode. Zim also vowed to destroy that bee, but never did.