At the middle school, Lincoln, Clyde, Zach, Liam, Rusty, Stella, and the rest of the sixth graders are going on a field trip to a rock quarry. Mrs. Salter will be chaperoning them, but the gang is confused on why Mr. Bolhofner has to tag along. This causes the gang to bring up rumors that they have heard about him from the other students, like how he's allegedly an escaped convict, a cannibal nicknamed "Skullhofner", and a mobster. At that moment, Mrs. Salter informs the remaining students that she accidentally called in the wrong bus, so they won't have enough seats for all the students. Mr. Bolhofner offers to bring the rest of the students in the school van. Clyde, Zach, Liam, Rusty and Stella are afraid to ride along with Mr. Bolhofner, but Lincoln assures that the rumors are false, when suddenly, Mrs. Salter urges the bus driver to leave before Bolhofner comes back. After using a crowbar to pry the van door open, the gang jumps in.
As Mr. Bolhofner drives to the rock quarry, he tells the kids some of his pastimes, like movies, games, and hunting small prey. Suddenly, the group hits a roadblock, as a truck shipping Flippee syrup has rolled over, and syrup is spilled everywhere. Mr. Bolhofner opts to take a shortcut through the woods, having driven through it before. As the group take a stop so that Clyde can throw up (with Zach thinking he's acting), the gang is still worried that all the rumors about Bolhofner are true, but Lincoln is still hopeful that he's not a bad guy, even if he finds a few things off-putting. When Clyde comes back, Mr. Bolhofner tells the gang that the filed trip is canceled because the bus with the sixth-graders is stuck in Flippee syrup, and offers to drive the gang back home. As the relieved gang jumps in, the rear right tire pops, and Mr. Bolhofner doesn't have a spare. He says that they head to his cabin in the woods, so they can use the landline to call for help.
After trekking through the woods, the gang arrives to the cabin, and Mr. Bolhofner attempts to use the phone, but the phone's out. Realizing they might have to stay the night, Mr. Bolhofner goes to his shed to pick up firewood. A few seconds after Mr. Bolhofner leaves, Lincoln, seeing the numerous amounts of tools and weapons in the cabin, is now convinced that all the rumors are true and attempts to escape, but Mr. Bolhofner has boarded the door from the outside. Because of this, Lincoln says that must escape no matter what.
First, the gang attempts to trap Mr. Bolhofner by having him trigger a tripwire to drop a quilt on him so that he'll fall onto the lard covered floor so that he'll become tangled up enough to give the gang enough time to escape. As the gang hides, they notice Liam is missing. Liam exits the bathroom, and unknowingly trips the tripwire, causing the quilt to fall onto him and knock a moose head onto his head. At that moment, Mr. Bolhofner arrives with firewood, and is merely annoyed by the shenanigans he sees. Later, everyone sits around, the gang spots the key on Mr. Bolhofner's pants, and attempt to retrieve it. The gang suggest that Rusty practice some dance moves with him, but the gang is unable to grab the key. Later, the gang has a new plan. Lincoln successfully retrieves the key and trap Mr. Bolhofner in the cellar. When the key breaks, the gang uses the moose head to ram the door down and attempt to run for it, just as Mr. Bolhofner breaks out of the cellar. As the gang runs, they hit a dead end, and as Lincoln records his last will on his phone, Mr. Bolhofner arrives, and suddenly pounces on a bear that was about to attack the gang. After fighting it off, Mr. Bolhofner scolds the kids for locking him in the cellar and getting themselves in a dangerous situation. This causes Rusty to admit that they heard a bunch of rumors about him and believed they were true, causing Mr. Bolhofner to say that the rumors are false, as the students are just making assumptions about him.
Back at the cabin, as the gang warms up by the furnace, Mr. Bolhofner says that his shed might have a spare tire, and decides to wait outside so that the gang won't have to be scared of him. After stepping out, the gang feels bad that they treated the teacher with disrespect, and wish there was a way to show the whole school what Mr. Bolhofner is really like. This causes Lincoln to get an idea.
The next day, the gang shows the students Lincoln's phone footage of Mr. Bolhofner fighting off a bear, and tell them that he's not as bad as he looks. Mr. Bolhofner enters the cafeteria, and the gang attempts to show off "Mr. Coolhofner", but the teacher tells the students to head to class. Just as the gang is about to exit, Mr. Bolhofner stops them to say thanks for ending the rumors about him.