Ickis, Krumm and Oblina get trapped in a garbage compactor and the only thing they can do is bicker. As their impending doom approaches, they remember their first days at The Academy.
The Academy is gearing up for the Scaring Olympics. The Gromble wants desperately to win the competition and is pushing his students to do their best. Unfortunately, Krumm has swallowed an Indian feather that is tickling him on the inside.
A hungry parasite named Sal invades Oblina's stomach, causing her to eat everything in sight. Ickis and Krumm shrink down to Sal's size, enter Oblina's body and battle it out with him inside Oblina's expanding stomach.
Ickis is perpetually late for class, so The Gromble hangs a big clock around his neck to remind him to be on time. When Ickis rewinds the hands on the clock, he discovers that he can turn back time.
Ickis discovers as easy way out of getting his homework done. By tapping into humans' phobias, he is able to bring scare after scare to class with little or no effort. That is, until The Gromble sends him to a phobic-free human to scare.
The Gromble assigns Ickis to be "pair-scare" partners with the dreaded, unpopular Zimbo. Ickis and Zimbo are miserable with the match and instantly start fighting.
When Krumm is forced to wear glasses to correct his inexplicably blurry vision, he finds himself the object of mocking on the part of the other students. Krumm tries to go without his glasses, but he and all the students learn their value when a bespectacled Krumm saves a group of monsters after a scare goes wrong.
Shortly McGinty, arch-criminal and master of disguise, escapes from prison and leads the police on a chase that takes him to the dump, where the cops mistake Ickis for McGinty and haul him off to prison.
A substitute teacher arrives, announcing that The Gromble has "gone away" and that he will be taking over. The substitute lets the students do whatever they want - even garbage fights are allowed!
The monsters are overjoyed when the famous Loch Ness Monster pays a visit to The Academy to give a guest lecture. Unfortunately, the rowdy, boisterous Scotsmonster gets on everyone's nerves by relentlessly singing Scottish songs, dancing and re-enacting his famous scares.
Ickis, Krumm and Oblina get trapped inside a nuclear power plant when they accidentally set off a warning device closing down the entire facility. Seeing the three monsters on a monitor, one of the plant workers mistakes them for three plant employees. A team of highly trained doctors don protective clothing and go inside the facility to bring the "employees" out to safety.
When a group of "cool" girl-monsters shuns the obsessively rule-bound Oblina, she transforms herself into Oblina The Rebel--breaking every rule she can.
Through a series of misinterpretations, Krumm is convinced that Oblina has a crush on him. Krumm gets paranoid about what this will do to their friendship and tries desperately to avoid her.
Oblina loses her lips when they get caught on a construction barricade and ripped off. The lips are found by would-be model Lucy Schmeeler, who glues them on and is proclaimed a sensation by Modelling Agency Owner Dietrich DuChamp.
A case of mistaken identity leaves Ickis thinking six lobsters are actually six monsters. He saves them from being served as dinners and promises to see them safely home.
Simon the Monster Hunter builds the ultimate monster hunting machine; The Simon-Mobile, in an attempt to capture a real monster. When the monsters get wind of this, they build a machine entirely out of garbage and go head to head battle with Simon. With The Gromble at the helm, the monsters emerge victorious.