List of Invader Zim episodes

Invader Zim is an American animated television series that was produced by and aired on Nickelodeon. The series revolves around an extraterrestrial named Zim from the planet Irk and his ongoing mission to conquer and/or destroy a dark and satirical version of the Earth. His various attempts to subjugate and destroy the human race are invariably undermined by some combination of his own ineptitude, his malfunctioning robot servant GIR, and his nemesis Dib, one of very few humans not oblivious enough to be unaware of Zim's identity.

Invader Zim was first broadcast on March 30, 2001. The show was targeted at children in their early teens, and met with critical acclaim. However, after the first season the show's ratings began to suffer. Before the second season was completed, Nickelodeon cancelled the series, leaving at least sixteen episodes and a planned television movie series finale unfinished. Because of its continued fan base and above average DVD sales since cancellation, Invader Zim has been called a cult hit.

The series consists of a pilot episode, 46 episode segments, and at least 17 episodes that were in production at the time of the series' cancellation. As of August 19, 2006, all 46 episodes have aired on television and been released on DVD. On December 24, 2011 the pilot episode finally aired on television. 38 episode segments were originally broadcast in pairs, each 12-minute episode segment debuting in the same half-hour. There are eight double length episodes. This list is ordered by the episode order in the DVD releases, with broadcast dates noted. Almost every episode was directed by Steve Ressel; the only exception is the pilot, which was directed by Jordan Reichek.

Original Pilot: 1999; 2011
Billy West was the voice of Zim for this episode only. This episode was also created as an animation test. Richard Horvitz was chosen for the series role after the pilot was shown to Nickelodeon because West's voice was too recognizable from Futurama, according to Invader Zim creator Jhonen Vasquez's DVD commentary.

As a part of Nicktoon's Winter Funderland, the pilot aired for the very first time on TV twelve years after it was made and seven years after it was first officially released on DVD. Satellite company DirecTV marks the episode's airdate "(2011)", meaning that this special did not air in 1999 as it was rumored. Also, the voice of Zim repeatedly changes throughout the episode, meaning that the voice of Billy West was replaced, however, some of his voice acting is still on the episode at some times.

Season 2: 2002–2006
The second season of Invader Zim aired in 2002. After the season's first episode, the show was cancelled and the episodes that had been completed prior to the cancellation were not shown. The remaining finished episodes were released on DVD in 2004, and finally aired in 2006 on Nicktoons Network. Season 2 was not completed.

DVD release
47 of 68 episodes (not including the pilot) of the completed Invader ZIM series have been released on DVD, along with the pilot, an alternate cut of The Most Horrible X-mas Ever, and audio from seven of the unfinished episodes. Later, a DVD boxed set including both the seasons was added to the market. This came with a box shaped like Zim's house with a GIR figure, 46 episodes and all 6 DVDs. The last "new" episode aired in 2011.

An "Invader Zim Seasons 1–2" DVD was released on May 4, 2010 by Amazon.com as an on-demand title. These DVDs contain all the episodes, but do not have any commentary or special features.

An Invader ZIM DVD was released on February 22, 2011 titled "Operation Doom", which features the highest-rated episodes of the series.