Toonami is a programming block on Adult Swim, formerly aired on Cartoon Network,that has been produced by Williams Street since it's inception. It airs every Saturday, at varying times. The block takes the place of the previous block, and similar to AcTN, the majority of the shows aired shows are Japanese, however, unlike the previous block, it has aired non-Japanese programming.
On April 1, 2012, Adult Swim aired Toonami for April Fools' Day. After the scheduled Bleach airing, the network aired shows such as Dragon Ball Z, Mobile Suit Gundam Wing, Tenchi Muyo! Ryo-Ohki, Outlaw Star, and YuYu Hakusho. The following day, Adult Swim posted a message on Twitter, stating, "Want it back? Let us know. #BringBackToonami". On April 4, Adult Swim followed up by stating, "#BringBackToonami We've heard you. Thank you for your passion and interest - stay tuned." On April 8, Adult Swim aired two bumpers about the Toonami tweets and answered with "[we're listening]" and "[we're looking into it]".
On May 16, Adult Swim posted a message on Facebook announcing that Toonami would return on May 26. The block premiered with a line-up of Bleach, Deadman Wonderland, Casshern Sins, Fullmetal Alchemist Brotherhood, Ghost In The Shell: S.A.C. 2nd Gig, and Cowboy Bebop.
Toonami would expand to a full six hours on October 6, and Sym-Bionic Titan and ThunderCats would be added to the block, becoming the first shows not produced in Japan on the Adult Swim version of the block.