This episode starts out with Zim at a table eating lunch. He looks picks up a pea, sniffs it, and throws it back down disgustingly. Behind are some mashed potatoes that are on the ground, and a kid walks in it, slips, and hits Zim in the head, knocking his face in his lunch. He screams and jumps around on the table, while everyone is looking at him.
A popular girl is talking to her friends, and she says that the new kid is a freak, and that he's been there long enough to make some loser friends, like the creepy kid Dib, or the rejects in the corner. She asks what kind of kid doesn't have friends, and says that it is so inhuman.
Zim gets an image of him in a green tank, and this woman reporter asking how they knew he was an alien. He replied by saying that he didn't have any friends. Zim looks around at the kids playing and sharing things with each other, and then looks at Dib.
Zim looks at the "rejects" the girl was talking about in the corner, and says that he is looking for a friend. He was about to ask one kid, but he said he was born with webbed fish toes, like some kind of horrible fish boy. Zim freaks out and walks away.
He goes to another kid, and says "would you-" and the kid screams and runs off. He says, "human filthys! These humans should be honored to be even considered being friends with ZIM!" He sees three kids in the corner looking at him, and he asks, "who among you think they deserve to be my, best friend?" They don't say anything.
Zim decides to make some tests to see who's the best. Test number one is an absorbency test. He pours milk on the table and rubs their heads in it. The girl with braces and the kid with the smiley tee-shirt didn't do anything, but the red-haired kid absorbed the milk.
The next test is an electrical conductivity test. He pulls out two electrical maker things and shocks all the kids. The girl and the guy with the smiley shirt both are fried, but the kid with the red hair is perfectly normal.
The next test, he says he will test... and pulls out a taxi car and a stuffed squirrel. It doesn't show what he did with them, but the only kid that is un-harmed is the red-haired boy. Zim asks his name, and he says it is Keith. Keith said that he was so happy, and hugged Zim. He pushes him away with his finger and says not to touch him.
Zim is dragging Keith by the collar down the lunch room. He goes to the table where the popular girls were sitting, and announced that he had a best friend, Keith. The girl tells Zim to get lost, and Zim says, "Very well, I'm getting lost, but notice I'm getting lost with my best friend, and he leaves.
At recess, it shows the fun that Keith and Zim had playing tetherball. When they won, they did this gay little dance, and everyone was watching them. During art class, he comes up to these girls and shows them a picture of Keith and Zim. Keith shows up behind him with a painting of them two. It shows them walking the halls, saying hi to everyone, and then Keith accidentally ran into Zim, and Zim pushed him.
Zim and Keith are walking home, and Keith is talking about going to the circus, how much he loves it. Zim tells him that he doesn't need him as a friend anymore, now that the world seems satisfied with their companionship, but Keith asked if he had any video games, and Zim said yes, and shut the door. Zim looks at GIR, watching the scary monkey show, and Keith slides of picture of him and Zim from under the door.
Zim gets a call from Keith, and Zim tells him that he doesn't need his services anymore, but in the middle of the sentence, there is another call, and it is Keith again, saying that he's going to love the circus. Zim rips the phone out the wall, and looks out the window and sees Keith riding his bike by his house. Zim shuts the blinds and yells for GIR. He comes falling off the ceiling, and Zim tells him that he is going to his lab and to not let anyone in the house.
Zim goes down to his lab, and the doorbell rings. GIR thinks it's leprechauns, and goes to the door. Zim comes up from his lab, and Keith is making some bacon. He looks at GIR, who's plate is piled with waffles. Zim yells at him to get out of his house, and he pushes him to the front door. Keith says that they can walk to school together, and Zim said that he was sick and he was going to school today, and throws Keith out the door. GIR walks outside and takes the bacon. Keith says that they should throw a surprise party to cheer him up, and GIR get excited. Keith says that he is going to get a whole bunch of kids from school, and tells GIR not to tell Zim.
Zim is sitting on the couch watching TV, when GIR comes in with a whole bunch of party stuff. He puts it on the table, but the bag falls over, revealing the contents to Zim. Zim asked what GIR was doing, and he said nothing. Zim was like, "nothing, or something?" and GIR said, "I can't take it, you're too smart for me. Keith is planning a surprise party for you and he is going to bring all the kids from school because he loves you, and he falls on the floor, and says "He loves you so much," and then he gets up and says, "I'll make him a cake!" Zim said that he is bringing all the children to his secret lair, and asks GIR if he knew what that means. GIR said, "Yes... wait a minute... no!" and and Zim says that it means that mission is in jeopardy. GIR said "aw man," and went back to stirring the batter for the cake. Zim said that he must stop him, because if he succeeds, then the whole population of earth will show up on his doorstep.
Meanwhile, back at school, Keith is passing out fliers for Zim's party. He gets to the popular girl from the beginning, and she asked who Zim was. He said it was the green kid, and she said, "oh, the freak? With that one kid that makes him even freakier? I don't think so." and everyone crumples up their fliers and throws them at Keith. He sees the unpopular kids sitting at the table in the back, and smiles.
Back at the base Zim is working on something, and he has a vision of kids coming to Zim's house with burning stakes, and then a vision of the scientist from his earlier vision and kids crowding around his alien form.
School gets out, and Keith runs out screaming PARTY! Zim looks at the clock and see's that it is two minutes past three, and tries to hurry up with whatever he's doing. Keith and the unpopular kids are running to his house in slow motion, and Zim is trying to finish up. GIR is stirring the cake batter. Zim's finally done, and Zim reveals his creation.. a present.
Keith is telling the kids to wait on the corner, and telling them that when Zim comes out, to yell surprise. Keith runs in and sees Zim standing there with a present in his hand. Zim gives Keith the present, and he opens it. There is a big ball in there with arms that are used to gouge out Keith's eyes and replaces them with new ones with red pupils. Zim has Keith under his mind control, and tells him that when he snaps his fingers, the next living thing he sees he will believe to be his best friend. Zim snaps his fingers, and the first thing that Keith sees is a squirl. Keith sees it as Zim. He runs outside after the Zim squerl. He shows his friends the squirl, and tells them that that is Zim. Keith runs up on the side of the house to chase the squirl, but the squirl mauls him, where Keith is never heard from again... I think.