Dexter's Laboratory is an American animated series created by Genndy Tartakovsky for Cartoon Network. It follows Dexter, a boy-genius and inventor with a hidden laboratory in his room, which he keeps secret from his parents. He is in a constant battle with his older sister Dee Dee, who always finds a way to get inside Dexter's lab and inadvertently foil his experiments. Dexter also engages in a bitter rivalry with a fellow boy-genius named Mandark, who is Dexter's neighbor and classmate. Prominently featured in the series' first two seasons are segments featuring superhero-based characters Monkey, Dexter's pet lab-monkey/superhero, and The Justice Friends, a trio of superheroes who share an apartment.

Tartakovsky pitched the series to Fred Seibert's first animated shorts showcase What a Cartoon! at Hanna-Barbera, basing it on student films Tartakovsky produced at the California Institute of the Arts, and four pilots aired from 1995 to 1996. Viewer approval ratings led to a half-hour series, which initially ran for two seasons with 52 total episodes from April 27, 1996, to June 15, 1998. On December 10, 1999, a made-for-television movie titled Ego Trip aired as the intended series finale, and Tartakovsky left to begin work on Samurai Jack.

In 2001, the series was revived for two more seasons containing 26 total episodes, which began on November 18, 2001, and concluded on November 20, 2003. Due to Tartakovsky's departure from the series, the new seasons were made under Chris Savino and a different production team at Cartoon Network Studios. The revival's animation was created with digital ink and paint instead of the previous seasons' cel animation style.

Dexter's Laboratory received critical acclaim and became one of Cartoon Network's most successful original series. During its run, the series won three Annie Awards, with nominations for four Primetime Emmy Awards, four Golden Reel Awards, and nine other Annie Awards. The series is notable for helping launch the careers of animators Craig McCracken, Seth MacFarlane, Butch Hartman, and Rob Renzetti. Spin-off media include comic books, DVD and VHS releases, music albums, collectible toys, and video games.

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