Invader ZIM, Nickelodeon (reruns on Nicktoons Network)
IMDb; Nickipedia; Nicktoons; TV.com; TV Tropes; Wikia; Wikipedia
For more links see cartoon links.
This show is insane. And therein lies its genius! Okay, here's the basic plot. Zim is a member of the Irken race, who send out Invaders to different planets to conquer them and add them to the Irken Empire. Zim is a nuissance who the Almighty Tallest just want to get rid of. He kind of ruined Operation Impending Doom I, after which he was banished to the planet Foodcourtia. When the Tallest called all the Invaders together to announce Operation Impending Doom II, Zim, who was not invited, decided to quit being banished. The Tallest had finished handing out conquest assignments and robot SIR (Standard-issue Information Retrieval) units to all the Invaders, when Zim showed up. To get rid of him again, the Tallest cobbled together some old junk and called it an advanced SIR unit. It called itself GIR, but it doesn't know what the G is for. GIR is the coolest! He's stupid and has a short attention span and eats too much junk food and watches too much TV and stuff. He's so cute! Gotta love the GIR. Anyway, the Tallest assigned Zim and GIR to some remote uncharted area they, the Tallest, knew nothing about and weren't at all interested in. They never expected to hear from Zim again.
But, Zim ended up on Earth, where he wears a pathetic disguise that only a kid named Dib sees through. Zim attends elementary skool. He's in Ms. Bitters' class with Dib. Dib is a conspiracy nut who tries to expose Zim as an alien, but all the other kids just think Dib is weird and crazy and annoying. He has a sister named Gaz who thinks the same of him, and while she may be aware that Zim is an alien bent on conquering the Earth, she doesn't really care. She just wants to play her video games and be left alone. I love Gaz! Their father, Professor Membrane, is a brilliant scientist who spends all his time in his lab and is almost never seen in person, just his head on a hovering commscreen.
Anyway, Zim's always got some crazy scheme or other, and stuff. And um... the show's just insane and hilarious and so cool and great and wonderful and great and cool and crazy and hilarious and stuff. So watch it! I command you! Obey the fist!