Timmy introduces Chloe to Mark Chang to prove that aliens exist. But when Chloe convinces Mark to reveal his true form to the world, he's put at risk of being captured by government agents.
Timmy takes Chloe to the dump where they meet a disguised Mark Chang and Timmy tells him that Chloe doesn't believe in aliens. Chloe confirms this by affirming they don't exist, as Wanda tells her that Mark really is an alien who's just disguised to blend in. Timmy tells Mark that Chloe accepts all people as Chloe states that no matter what people look like they deserve to have acceptance. Mark is confused by her words, as Timmy orders him to change to his alien form as he uses his Fake-i-fier to transform to his alien form confirming to Chloe that he is an alien. Seeing this, Chloe screams as Mark reacts that he knew she would get freaked out but Chloe states it was because she just found out that aliens were real and that is very cool. She asks about his traits as he shows her and reveals he wants to style hair and shows his work as Timmy gloats to Chloe about her being wrong. Chloe shrugs off his gloat and states she sees Mark as a unique person
At school, Timmy wonders where Chloe is after she turned out to be wrong on something. Chloe arrives with the disguised Mark and alters her report to admit she was wrong by revealing Mark. However, Timmy has the fairies stop time, stating Mark will be captured by the government if he reveals himself but Chloe doesn't believe so and has time restart. She encourages Mark to reveal himself and he does, shocking everyone. Timmy wants to retreat before agents show up though it turns out most of the class are agents, shocking Chloe who sees she was wrong again. The kids are chased by the agents lead by Mrs. Crocker who erases her son’s memory for seeing too much.
Very soon, the group leave school and head to the streets but get separated with Mark and Chloe captured. Fortunately, Timmy has the fairies disguise themselves as aliens to defend them. Timmy then forces Mrs. Crocker and her agents to release the group. He also demands they let Mark live on earth in his alien form to style hair while leaving Chloe alone. Mark also demands for them to release his friends the Loch Ness monster and Bigfoot who were previously captured.