The story is A Day in the Limelight for Harry, Ron, and Hermione's Gryffindor contemporaries, Dean Thomas, Seamus Finnegan, Parvati Patil, and Lavender Brown, which takes place early in the school year during the events of Prisoner of Azkaban. It begins when Fred and George Weasley steal a curious board game from Filch's office. Not wanting to get caught, they give the game to Dean and Seamus, explaining that, as unremarkable Recurring Extras, Filch will be unlikely to suspect them. After they examine the game with Lavender and Parvati, Dean and Seamus decide to play a quick round with the girls to see what the game is like.
Dean Thomas and the Curse of Jumanji provides examples of:
- A Day in the Limelight: Normally pushed to the background in the novels, Dean, Seamus, Parvati, and Lavender get their own adventure in this story, and if they don't succeed, it may spell a premature doom for the rest of the characters.
- Alternate History: Thanks to Jumanji's built in reset button, the events of the story are this to the larger Harry Potter story. Try to imagine how the novels would have been different if during Harry's third year, Hagrid was killed, Pettigrew died before the truth could be discovered, and Hogwarts was completely destroyed.
- Animal Stampede: The same one from the Jumanji film. It's made of rhinoceros, elephants, and zebras.
- Artifact of Doom: The Jumanji game. Its powers are immense, even in the context of the Wizarding World. It even has the power to break all the protective enchantments of Hogwarts and destroy the castle
- Big Creepy-Crawlies: A few camel spiders come out of the game in Hagrid's hut, and are described as being the size of cats. Hagrid, of course, is very pleased.
- Chekhov's Gun: Fawkes and the Sorting Hat appear briefly in Dumbledore's office before Dean, Seamus, Lavender, and Parvati have to leave. They return during the climax.
- Climactic Volcano Backdrop: The only thing cooler than fighting a nundu with a sword? Fighting a nundu with a sword while the ground splits open, and lava erupts all around you!
- Everything's Better with Monkeys: The monkeys from the film appear. They trash Dumbledore's office before escaping into the rest of the castle.
- Full-Boar Action: The Tebos that appear outside Hagrid's hut. They gore him to death.
- Hungry Jungle: A very literal one swallows Hogwarts castle. As if it wasn't dangerous enough...
- I'm a Humanitarian: A group of monstrous cannibals comes out of the game.
- Man-Eating Plant: The yellow pods from the Jumanji film. None appear, but a few are mentioned trying to eat Marcus Flint and Fang the boarhound.
- Panthera Awesome: The penultimate thing to come out of the game is a nundu — a creature unique to the Harry Potter world (though is based loosely on the mngwa: an African cryptid). The nundu is described in Fantastic Beasts and Where to Find Them as a gigantic leopard with noxious breath that causes fatal illness.
- The Swarm: The first thing to come out of the game is a swarm of driver ants.