In order to really annoy his sister, Jen, Andy copies everything she says and does, including going to a school dance in a dress. Things become complicated when Craig, the popular school jock, falls for Andy (in a dress) over love-struck Jen.
It starts with a party, in which Andy in drag is dancing with Craig in a suit. Craig looks happy, but not Andy. Andy narrates that it is not what the audience thinks and he is an artist. Craig picks Andy up to kiss him, and then Andy freezes time, gets out of Craig's arms, and says that he is an artist but his medium is a bit unconventional and he is a practical joke artist. He gets out of his drag and says he is a pretty good practical joke artist and will someday be famous for it. He then gets back in his drag and says the dress belongs to his sister. He then snaps time back.
Spank is lying on his back, sleeping on the deck. Jen growls and says "When are you gonna stop imitating me?" Andy copies. Danny follows the Larkin siblings, and then Spank wakes up. He falls asleep and Jen walks over him again, calling Andy a complete waste of a human being. Andy copies. Danny counts down from ten, while Jen calls Andy a loser for imitating her, to which Andy copies her again. Just then Danny finishes his countdown and declares a new record: twelve hours of copying Jen, and one of Andy's most annoying pranks. Andy replies he's a pioneer of practical jokes. He then imagines himself as a pioneer, playing practical jokes. Jen says that one day he'll go too far. However Andy likes the idea of going too far and does a little dance while imagining having "finally gone too far". Jen just thinks Andy is stupid, but then Andy starts to copy her again. He then takes off his sunglasses. Danny asks if he is going to copy Jen for twenty-four hours. Andy says that older sisters are supposed to be annoying and the copying will teach her not to tell their dad that he was the one who put purple hair dye in the shampoo. He also likes to annoy Jen. Danny says to a sleepy Spank that Andy will probably break a world record. Mr. and Mrs. Larkin are on the couch, looking bored. Al is watching TV and Freida is reading. Jen walks by, telling Andy she's not kidding and to leave her alone. Andy copies. Al feels sorry for Jen, but Freida thinks it's nice that Andy is taking an interest in Jen's activities. Jen climbs the stairs, saying that Andy forgot what that night is. Andy climbs the stairs, copying. Jen says the school dance is that night and she is going in a tight, pink, strapless dress. Andy copies all of that except for the "in a". He then looks shocked. Jen doesn't think Andy will copy her wearing a dress. She then reclines on her beanbag, while Andy has stopped copying. However, Andy has not had enough, an imagines himself not knowing the meaning of "enough". Jen goes off to take a shower, while Andy sneaks into her bedroom and changes into the drag outfit we saw at the beginning. He has a bit of trouble in high heels. Jen leaves, followed by Andy. This confuses the parents. Freda wonders if Jen said goodbye twice, and Al wonders if it was Andy, and that just makes them laugh, but also makes them a bit nervous. Andy is outside, determined, but not liking the dress and shoes. Danny, in a suit, gives him a lift in his wagon/scooter. The boys show up at the dance. Danny thinks Andy looks pretty, but he is not flattered. Like and Leech see Andy, and think he's a girl. Andy narrates that Lik and Leech are the town's biggest bullies and will punch him if they figure out it's him in the dress and wig, but as its' "show time", they never will. Andy fake-flirts in a high voice, but then falls over, to be caught by Lik. Like jokes that Andy has "fallen" for him. Craig then knocks the bullies over and introduces himself to Andy, who he doesn't recognise, offering help. Andy doesn't like Craig very much. He thinks he's too arrogant, and doesn't like the smell of his aftershave. Andy says his name is Andrea, but all his friends call him Andy. He then pretends to be new and mysterious. ("I've just moved here from somewhere else" "Somewhere else. How mysterious." "I'm full of mystery".)
At the dance, which has a tropical theme, Jen wants to attract Craig, but Teri points out that Craig seems to already have a date. Craig and Andy, followed by Danny, enter. Andy and Danny wink and give a thumbs up. Danny tries to flirt with a girl, but then gets nervous. Teri asks who Craig's "new friend" is and Craig says "Her name's Andrea. She comes from somewhere else." Jen says Andy is annoying, and walks off to "have girl talk" with him. Jen yells at Andy for wearing her dress and says she'd drown him if the pool was deeper. Craig shows up with two plates of food. Jen then stands on Andy's foot. Andy then hands Jen the food and asks Craig to dance. The two boys begin dancing, which the others like, except for Jen and Teri. Jen throws down the food and Danny tries to ask Teri to dance, but is so awkward, she thinks he's having a seizure. Craig then starts to tango with Andy. That's where the audience left off. He thinks the prank was a success, but doesn't want Craig to kiss him. Andy tries to avoid being kissed, but the beads that he was using for boobs leak out of his (Jen's) dress. He says he is "leaking", which he tries to say means "crying" tears of joy, and goes to the bathroom. People keep slipping on the beads. However, Andy goes into the boys' bathroom and the boys there think he's a girl, so he's forced to go into the girls' bathroom. He goes in, acting awkward. A valley girl says to her friends that Andy is acting "psycho". Andy tries to squeeze through the window. However, Lik and Leech are at the bottom, so he goes back into the bathroom. However, the rest of the beads leak out and Lori trips over them. Andy stuffs the dress with toilet paper and helps Lori up. Andy has a crush on Lori, so he doesn't like being in a dress when he's alone with her. Lori thinks "Andrea" reminds her of Andy, however she still doesn't recognise him. Andy pretends to be related to, well, himself. Lori says to Andy that she thinks Andy (she doesn't recognise him) is immature. Andy says he/she thinks silly is cute, and Lori says she had hoped Andy would be there that night. Andy says that, well, himself, is on his way. This confuses Lori.
At the dance, Craig grabs him again to dance. Andy says there is something Craig should know, to which Craig thinks it's because "Andrea" has a crush on him. He then tries to kiss Andy, who tries to call Danny over. Andy then, as a ploy, dances with Danny, who doesn't like that the only person to dance with him is a boy in a dress. Jen then announces that the winners are "Andrea" and Craig and the prize is a romantic dance. Craig wants to kiss Andy. Andy doesn't have anything to say. He then reveals himself, pretending it was a prank Jen had played. This shocks everyone, including Craig, who thinks Jen is a freak for allegedly making him almost kiss her brother. This makes Jen mad, but Andy is satisfied.
Outside, Danny congratulates Andy. Then, Lori shows up, embarrassing Andy.