Previously on Detentionaire: Clips are shown from the previous episode, as Lee questions Tina, the DoD, and VP Victoria if they know Lynch, coming to the conlcusion they got to all of them. Next, how the machine pairs up couples for the dance and how Cam and Brandy answer their new phones. Lastly, it's shown how Inspector Blompkins expells Lee.
Blompkins has Lee sign a paper making him officially expelled. Barrage states that he will miss making him suffer as Blompkins tells him he passed his evaluation with flying colors. VP Victoria tries to stop him before Barrage sends her to his office. Meanwhile, Biffy is still trapped behind the secret door, as Cleaners come up. He pretends Lee is behind them, and as they are distracted, tackles them.
Lynch, in the gym, supervises how the decorations for the Dance are going, and receives a text message telling him that Lee has been expelled. He leaves, mad that it wasn't part of his plan, as he says they aren't done with his game yet. Tina tries to convince Brad that they're all being brainwashed through their phones, telling him how odd it is for him to think he "is too good for her" one minute only to ask her to the dance the next. She says that she faked answered her phone previously just to fool Lynch. Brad only believes her once he sees everyone answer their phones at the exact same time and ask the person next to them to the dance.
Chaz then comes up with 'Live Breaking News', announcing how Lee has been expelled as the camaras film Lee leaving through the corridors, watched closely by Barrage. Tina runs to stop him, leaving Brad mad that she choose Lee over him.
Holger runs out of a classroom and latches into Lee's leg, saying Lee must stay so that they could be friends forever until the "old men times" and then into the "ghost times". Lee tells Holger to get Cam so they can destroy as many phones as they can because they are brainwashing people, but before being able to tell him anything else, Barrage makes Holger go away with one of the Eye Bots.
Chaz keeps on commenting as Lee arrives to the front doors, saying that once he crosses over, there is no coming back as the whole school watches. Lee crosses the door and Tina arrives at this moment and chases after him as Chaz asks her questions until he crashes into the door. Mrs. Ping is scolding Lee inside their car telling him she will send him to boarding school either in Alaska or Siberia, whichever is colder and has more bears, they leave as Tina yells Lee's name.
Back at the Tunnels, Biffy is trying to get away from the two Hazmats as they shoot him. He manages to cristalized them just as The Red Tatzelwurm comes through an air vent and indicates for him to follow. Biffy grumbles that he likes Lee better.
In the field, Brandy is telling Cam what he is to do if he is taking her to the dance as Holger arrives and crashes into them. He tells them that Lee has been expelled and destroys their phones. Once destroyed, Cam and Brandy remember being brainwashed and run off with Holger to stop everything.
In his office, Barrage reviews the video tapes of all the times VP Victoria used the beef jerky to brainwash him and demands she tell him all that she knows. With her phone, she calls two hazmats and makes them fire at Barrage.
Back in Lee's bedroom, Mrs. Ping tells him that he is not allowed to use neither his phone or computer, saying he will remain in his bedroom with much shame as she returns to school. Lynch video calls and Lee asks if he is happy now that he was expelled. Lynch states that he is devastated that they won't be able to finish their game. Lee angrily asks him the reasons for setting him up with the prank and why he brainwashes people, with Lynch telling him to come back to school to find out. Lee says Barrage will kill him the moment he arrives, and Lynch shows him how Biffy is trapped in the vents with Blue Tatzelwurms, as incentive for Lee. Once Lee agrees to go, Lynch says that he will be waiting for him in his favorite room.
Lee tries to open his locked room as Tina calls from outside his window. Lee goes down the ladder as she questions him on the brainwashing. Lee destroys her phone and both set on their way back to school, promising to explain everything on the way.
Meanwhile, Cam, Brandy, Holger and Greta go to Barrage's office to try to use the PA system to tell everyone to hand in their phones. Brandy is doubtful that anyone will listen, and she and Cam start bickering. All four enter the office to find it destroyed, including all the systems. Cam gets an idea as they go through the corridors destroying the phones themselves. Lynch comes through the PA system with a game of 'Knock Knock' that Holger plays along to, despite Cam telling him it's Radcircles. Lynch tells them he has big plans for the Dance and asks them to stop smashing the phones. Cam tells him that he has messed with his mind too many times as Lynch taps into the remaining phones, making everyone move towards them holding their phones saying "It's for you" in a zombie manner, as they run away.
Tina and Lee have entered school as Tina reviews everything Lee has explained: how Lynch and Barrage are evil, that VP Victoria was on his side until she was brainwashed too, and how he never did the prank. Lee asks her if she is dissapointed that he's not some badboy prankster, to which Tina replies that she'll get back to him. They arrive at the secret entrance through the library as Lynch watches them.
Biffy is stuck in the air vents as the Taz tries to move him. Seeing Blue Tatzelwurms appear, the Taz brings Biffy one of the cristalizer weapons that he uses succesfully to trap the evil Tatzelwurms.
Cam, Brandy, Holger and Greta interrupt Mrs. Ping's class as they enter to escape the other students. When questioned, Cam says that she can continue and to ignore the banging against the door. At that moment, everyone's phones ring and despite Brandy telling them to stop, they answer anyway, and proceed to try to brainwash them aswell. Biffy chooses this moment to crash throught the vents, and cristalizes everyone, including Mrs. Ping.
Cam informs Biffy that Lee has been expelled and Biffy comments how the whole operation falls apart just because he's away for a couple of hours. Holger tells him that they must destroy all the evil brainwashing phones, and Biffy goes to the door only to realize his weapon is out of ammo. They block the door as Cam comments that they should save the President and the First Lady.
Lee and Tina, meanwhile, have arrived at room 113B, and even though they know it is a trap, they go in anyway. Tina is cristalized completely by Lynch as he remarks that their game is only for two players, cristalizing Lee partially. Lynch shows Lee his room full of doors so that they can play Knock Knock forever. At that moment, VP Victoria arrives, and chides Lynch for the Knock Knock compulsion. Lee realizes, once Victoria has Barrage brought in, that she is behind it all. Barrage tells Lee that Victoria has been using the school and it's students as her own personal lab. Lee states that Barrage is on his side, Victoria is evil and that Lynch is nuts, and everyone agrees that is pretty much everything.
Barrage continues to say that the Prank was her way of trying to get him fired and that Victoria was the only one not covered by the prank. Lee recalls that she had told him Barrage, herself and the missing teachers had all been in the same Brainwashing program in the past. Barrage tells him that the project had been canceled because they couldn't make people do something truly against their will. VP Victoria says that thanks to the students, the method has been perfected and that she can now make them do anything and proceeds to tell Lynch to gather the students, that the dance was starting at that moment.
Lee questions why they choose him to be their scapegoat, and VP Victoria explains that it was because he couldn't be brainwashed and thus, was not useful. At that moment, a false wall opens to a tunnel where two Reaper Mats appear to take them to Coral Grove, a place, according to Victoria, where they send people who know too much, like the old teachers and the principal, in other words, anyone from the old research team. The Reaper Mats take Lee, Tina and Barrage on board as Barrage starts to try to escape.
Back with the others, they have used the desks and chairs to block the door, while Cam and Brandy hide under a desk. As the students are called away to the dance, Biffy states that he gets bad vibes from it, as they all go to the Gym.
Being transported to Coral Grove via the tunnels, Lee questions why Barrage was always on his case if he knew the truth, and Barrage says it was because he never liked Lee disrespecting the rules, authority figures and other people's property, releasing himself, Lee and Tina in the process and getting their ride to go back. However, an alarm is triggered and more Reaper Mats arrive. Barrage tells them to go stop Victoria as he deals with the robots, even though their powers are magnetic and he is half robot. Lee and Tina leave as Barrage is overpowered and shut down.
In the Dance, everyone is shown dancing, while VP Victoria talks to 5 shadowed figures (The Council), who asked her if she has them under her control and the past problem of not making them do something truly against their will. She replies by showing how everyone is dating outside their cliques, and that the technology is perfected. Biffy, Cam, Holger, Brandy and Greta get up into the stage, and Cam tells everyone to throw away their phones, but is ignored because the music is too loud. Victoria, using her phone, makes everyone go after the five of them. Brandy is taken as the others are quickly sorrounded.
In room 113B, Lynch watches as Greta is brainwashed just as Lee and Tina arrive. Lee tries to tackle him but falls, and as Lynch runs into the room full of doors, he tells Tina to try to shut down the machine. Lee tries different doors with no results as Lynch tries to get him to play along. Lee finally finds him through the trail Lynch left because of the nut shells. Lee grabs him and tells him to shut down the machine, but Lynch distracts him by asking if he would like to know the real reason he was chosen. Lee retaliates by saying what VP had explained, that it was because he couldn't be brainwashed. Lynch explains that there is much more, that Lee didn't belong in any clique, that apart from his nobody friends, no one would miss him, since he was a loner. He asks who would care, and Tina comes over to say she would.
Lynch tells them they're missing the show, as the screen shows how an already brainwashed Holger manages to get Cam, as Biffy tries to run. Lynch uses their distraction to get away, telling Lee they would have to finish their game another time.
Lee and Tina arrive at the gym to see Biffy barely holding his own against other students. VP Victoria tells The Council that the students who resist just need peer presure, and is surprised to see Lee and Tina up in the stage. Lee plays the Prank Song and tells everyone to snap out of it. But as he tries to tell them not to answer their phones, they do so, and are under mind control again. Victoria steps out of the shadows and shows she is controling everything with her phone. Tina puts on the Prank Song again but seeing that it has no effect, Lee tackles Victoria to the ground, knocking away her phone. Tina tells everyone to throw their phones away and puts on normal music. Out of mind control, Holger tells everyone to dance, destroying the phones in the process.
Victoria tries in vain to get them under her control, saying she is their Vice Principal, to which The Council says she isn't anymore and one of them grabs her arm. Another continues to say that while the project shows promise, it isn't up to Mann, Wurst and Finnwich level and various Reaper Mats arrive to take Victoria away.
One of the Council Members is revealed (Cassandra McAdams), as she comes forward and puts on the Prank Song once more, telling everyone that they will forget all that had occurred, remembering only the dance. When questioned by Lee, she says she is correcting things, and that everything had been taken care of, saying Lee had done a great service to The Council by exposing everything, and that it wouldn't go unnoticed. She tells him to be a kid and to enjoy the dance before leaving and putting on normal music.
Biffy comes up and tells Lee that it was weird, commenting how one of the Council members didn't look human. Tina arrives asking Lee what had happened, to which Lee replies he didn't even know where to begin.
Biffy goes to Kimmie, asking her if she would like to dance, to which she answers yes. As Lee and Tina walk, Holger is shown dancing with Greta, while Cam asks Lee if they had won. Lee says that he believes they did and asks Tina to dance. Up in the rafters, a shadowed hand is shown pulling a lever, the lights go out and everyone screams, thus implying that another Prank was pulled before the episode ends.
The motif from The Cam-didate is continued - Chaz calls Tina "Lee's secret girlfriend"
Chaz asks Tina about Lee's hair - continuing the recurring joke of the series
As a punishment for Lee being expelled, his mother plans to sent him to a boarding school in either Alaska or Siberia. Her final verdict on that matter is to be based on which county is "colder and has more polar bears."
Of interesting note of the two countries only Alaska has bears while Siberia is the one that's colder.
This episode continues directly into Return Of The Ping, whereas most episodes start on a new day.