Animaniacs ran for 99 episodes between 1993 and 1998. It was the second animated series (Tiny Toon Adventures being the first) produced by the collaboration of Steven Spielberg and Warner Bros.
Animaniacs had a large cast of characters, separated into individual segments, with each pair or set of characters acting in its own plot:
The Warners Brothers, Yakko, Wakko, and Dot (The Warner Sister), were three cartoon stars from the 1930s that were locked away in the Warner Bros. water tower until the 1990s, when they escaped. After their escape, they often interacted with Warner Bros. studio workers, including Ralph, the security guard; Dr. Otto Scratchansniff, the studio psychiatrist, and his assistant Hello Nurse.
Other featured characters include Pinky and the Brain are two genetically altered laboratory mice that continuously plot and attempt to take over the world. Slappy Squirrel is an aged cartoon star that would easily outwit antagonists and educate her nephew, Skippy Squirrel, about cartoon techniques. Additional principal characters included Rita and Runt, Buttons and Mindy, Chicken Boo,Flavio and Marita (The Hip Hippos), Katie Ka-Boom, a trio of pigeons known as The Goodfeathers, and Minerva Mink.
The Warner siblings and the other characters lived in Burbank, California. However, characters from the series had episodes in various places and periods of time.
The Animaniacs characters interacted with famous people and creators of the past and present as well as mythological characters and characters from modern television.
Andrea Romano, the casting and recording director of Animaniacs, said that the Warner siblings functioned to “tie the show together,” by appearing in and introducing other characters’ segments.
Each Animaniacs episode usually consisted of two or three cartoon shorts. Animaniacs segments ranged in time, from bridging segments less than a minute long to episodes spanning the entire show length; writer Peter Hastings said that the varying episode lengths gave the show a “sketch comedy” atmosphere.