Alexander is used to finding monsters everywhere in Stermont, but now the school is being turned into an icebox by giant meat-eating vegetables--and his friend Rip has gone missing.

Alexander's class is going on a field trip to an amusement park called Safety Land with really slow, boring rides--but this is Stermont, and when a weird magician tells Alexander and his friends that the roller coaster is haunted things start to get a lot more interesting.

Since the Notebook of Doom was stolen Alexander and the other monster hunters of Stermont Elementary have been operating without its assistance and now they are confronted by a large and stinky monster with eight powerful noses that can deliver a slimy sneeze with the power of a cannon--and somehow they must figure out its weakness.

Alexander and his new friend, Rip, are worried that the worms the rain has brought out are really the megaworms that Notebook of Doom describes but they soon discover that the night crawlers are trying to warn them about the monster tunnel fish that are threatening Stermont Elementary.

The Notebook of Doom is missing and Alexander and his fellow-monster hunters, Rip and Nikki, are convinced that the boss-monster has it; but is that monster the mysterious Principal Vanderpants, who is certainly behaving oddly, or someone else--and they need to figure that out quickly because a mistake could have deadly consequences for Stermont Elementary.

In the year since Alexander and his father moved to Stermont, he and his friends in the Super Secret Monster Patrol of Stermont Elementary have defeated all kinds of monsters, but now they face their greatest challenge, the boss-monster who has kidnapped fellow monster fighter Ms. Vanderpants and stolen the Notebook of Doom--and they have to do it before Alexander turns eight and stops being able to see monsters.