Dexter's Laboratory.

About Dexter's Laboratory

Dexter's Laboratory is an American animated science fiction television series created by Genndy Tartakovsky for Cartoon Network. The series follows Dexter, an enthusiastic boy-genius with a science laboratory in his bedroom, which he keeps secret from his unsuspecting parents. Dexter is at constant odds with his older and more extraverted sister Dee Dee, who regularly accesses the laboratory and inadvertently foils his experiments. Prominently featured in the first and second seasons are other segments focusing on superhero-based characters Monkey, Dexter's pet lab-monkey with a superhero alter ego, and the Justice Friends, a trio of superheroes who share an apartment.