Sealab 2021 is an animated TV show in the US. This show is shown on the Adult Swim programming block on Cartoon Network. The premiere for this series was on December 21, 2000 and the series ended on April 25, 2005. Sealab 2021 is one of the four first Williams Street Series' that was shown on Adult Swim in 2000. The other three shows were Harvey Birdman, Attorney at Law, The Brak Show, and Aqua Teen Hunger Force. Like the Adult Swim series' Harvey Birdman, Attorney at Law and Space Ghost Coast to Coast the show Sealab 2021 is a spin-off of a 1970's Hannah-Barbara cartoon, Sealab 2020.