Zack falls into Mr. Munk after walking through the door, and Zack just disappeared and he finds himself inside Mr. Munk's body. He was controlling every movement of the headmaster's body. He gathers up his team, Spencer and Cam and tells them the great news. He started his fun by getting Vernon in trouble, and then, he told the students that that they could fool around during breaks between classes. He then returned to Mr. Munk's office, and continues to document fake and funny information about Vernon (such as picking other people's noses).
Mr. Mantueffel arrives at the school and inspects the school and announced that the school would be shutting down due to the Headmaster's poor job at keeping the students under control.
Zack, Spence, and Cam who did not want to be separated to put in different schools, tried to devise a plan (getting Zack to transform back from Mr. Munk), but nothing could stop the children's havoc.
As a last resort, Zack read a discipline book, and used it to discipline the students, and finally, the school was back in order, and Mantueffel decided to cancel the shutting down process of Horace Hyde White. When Zack walks out of Mr. Munk's office, he was released from Munk's body and sent back to his body (Spencer realized that Zack had to go through the other way, through the door to reverse the Zack File) and Mr. Munk gave Spence and Cam detentions for pushing Zack into him.