The Nightmare Beings

The Nightmare Begins" is the 1st episode of the first season of Sponge & Invader.

Part 1
The Irkens are a race that desire universal domination. Their leaders, Almighty Tallest Almighty Tallest Red and Almighty Tallest Purple, have just begun assigning the Invaders their missions for Operation Impending Doom II in the Convention Hall planet, Conventia (The Great Assigning). However, the most dreaded and infamous Irken ever to live, Zim, arrives in hopes of getting an assignment of his own. Zim was banished from the Irken Empire and sent to work on Foodcourtia when he blew up the other Invaders during Operation Impending Doom I. "Quitting" his banishment once he hears about the new Operation, Zim begs for an assignment and the Tallest reluctantly send him to a planet outside the reaches of the Empire of no real interest to the Irkens, which turns out to be Earth. After receiving a poorly-constructed SIR Unit made out of garbage named Gir, Zim begins his long journey to his "mission". Little does he know, however, that an Earth child has tuned into the meeting on Conventia, and is now alert for an alien invasion.

Part 2
Six months later, Zim finally arrives on a planet called Earth. He lands and creates a human disguise for himself, and a dog costume for GIR. Zim then sketches a picture of a "normal" human house into a capsule with a drill, which bores into the Earth and creates a huge underground base, waking up the entire neighbourhood in the process. Zim then enters his new base and searches for a place to learn about the weaknesses of the planet.

Ultimately, he decides to join the local Skool. His disguise fools all of the students, except Dib, who tries to prove to his classmates that Zim is an alien. However, they don't believe him, so Dib attempts to capture Zim himself with Alien Sleep Cuffs.

After a lengthy chase, Zim calls GIR and has him take him back to the base. However, GIR leaves a trail of smoke behind that Dib follows. Zim hides inside his house, while Dib stands outside and vows to expose Zim for the alien menace that he is. However, the robotic gnomes in Zim's front yard destroy Dib's cuffs in the middle of his rant. Slightly discouraged, Dib decides to return home, but says that he will be back.

Zim, unconcerned about the human, dusts himself off, and contacts the Almighty Tallest (who are shocked that he is still alive), informing them that he is working hard on his mission and would take care of the humans before the armada even reached the planet. As the transmission ends, the two Tallest look at each other with dread in their eyes.

Trivia

 * This is The first two parter episode that being the show.
 * Being the pilot, this is the first appearance of Zim, Gir, Dib, Gaz, Almighty Tallest, Professor Membrane, & Ms. Bitters.