Sheen's a turbocharged, hyperactive 4th grader with an attention span of 0.4 seconds. His best friend back home is boy genius Jimmy Neutron. He's got a passion for life, TV, guacamole, and a superhero called Ultra Lord. He isn't the best student; in fact, it's his third year taking the 4th grade. But what he lacks in common sense and focus, Sheen makes up for in burning curiosity and loads of energy!
One day, disobeying Jimmy's specific instructions ("Sheen, Do Not Touch This Rocket!"), Sheen touches a rocket and goes flying into space! He lands on a strange planet called Zeenu, where the grand leader thinks that Sheen is destined to bring peace, prosperity, and eternal joy. After the Emperor promotes Sheen to be his #1 Royal Advisor, Sheen gets to do a ton of fun stuff, like battling man-eating creatures and throwing wild parties. Even when the evil villain Dorkus tries to destroy him, Sheen's crazy ways almost always save the day. In fact, Sheen has so much fun on Planet Zeenu, he may not be in such a hurry to get home after all.
Sheen crash lands Jimmy Neutron's 'borrowed' rocket on Zeenu, has tons of misguided adventures and deals with the planet's weird creatures and a stranded NASA-trained, talking chimp who joins Sheen on the quest to get home.