Trama

In 1996, in Brantford, New Hampshire, teenager Alex Vreeke (Mason Guccione / Colin Hanks) receives the Jumanji board game, found by his father on a beach. When Alex refuses to play it (saying that nobody plays board-games anymore), the game magically transforms into a video game cartridge at night. Opting to play, he is sucked inside the game, disappearing from the real world.

Twenty years later in 2016, as time continues to pass, is left the Vreeke family's house in a disheveled state and is avoided by everyone on the neighborhood. Old man Vreeke (Tim Matheson) still lives in the house and is considered to be crazy. Four students in Brantford High School are placed in detention together: Spencer Gilpin (Alex Wolff), who was caught writing essays for his former friend, Anthony "Fridge" Johnson (Ser'Darius Blain) (who is an athlete and is also in detention for the plagiarism. Fridge was worried about being dropped from the team due to his low academic scores), while Bethany Walker (Madison Iseman) (a typical teenager who is into her looks and lives her life on social media) and Martha Kaply (Morgan Turner) have both disrespected their respective teachers during class. Bethany was caught making a video call during a class quiz, and Martha refused to pair up for "catch" during gym class.

Spencer is a typical dork, who lives a "safe" life and wants to fly under the radar. They were ridiculed for their actions and are assigned by the school's principal (Marc Evan Jackson) to clear out its basement, the four find Jumanji, a multiplayer action-adventure video game. One of the playable characters (video game avatars) is inaccessible. When Spencer hits Start, the four are sucked into the game.

They find themselves in a jungle, each now in the forms of their game avatars. Spencer is a tough, muscular explorer named Dr. Smolder Bravestone (Dwayne Johnson) (an archaeologist and explorer who is Spencer's avatar. Bravestone's strengths are stamina, courage, reflexes, climbing, smoldering charisma, and boomerang throwing. He apparently has no weaknesses. He is the Archetypically masculine, intelligent, and courageous video game hero of the story)

Fridge is a short zoologist named Franklin "Mouse" Finbar (Kevin Hart) (whom he had selected upon misreading the name as "Moose") (a short zoologist and weapons specialist who is Fridge's avatar. Finbar is Bravestone's weapons valet (which he carries around in his backpack) and is skilled in cranial assault. His weaknesses are cake, strength, and speed)

Martha is a gorgeous commando and martial art expert named Ruby Roundhouse (Karen Gillan). (a commando, martial artist, and dance fighter who is Martha's avatar. Roundhouse is proficient in karate, Tai Chi, jujitsu and Capoeira, and her only weakness is venom, such as that found in various animals in the game. Similar to Bravestone, Roundhouse is the Archetypically intelligent, athletic, beautiful, and scantily clad video game heroine of the story)

Bethany is an overweight, male cartographer named Professor Sheldon "Shelly" Oberon (Jack Black) (a cartographer, cryptographer, archaeologist and paleontologist who is Bethany's avatar. Though Oberon's strengths are his fields of expertise, because of his obesity, his endurance is his weakness)

They soon realize that they are in a video game, and each have three lives denoted by 3 marks on their arms. If they lose all three, they will actually die. Each of their avatars also comes with special skills and weaknesses.

They learn from Nigel (Rhys Darby), an NPC (Non-Player Character, who can only provide Pre-programmed responses to questions) guide, that the big-game hunter (and Bravestone's former partner), Russel Van Pelt (Bobby Cannavale), has stolen a jewel, the "Jaguar's Eye", allowing him to manipulate Jumanji's animals. Nigel says that he stole the jewel from Van Pelt, and hands it over to Bravestone. To escape the game, the players must return the jewel to an enormous jaguar statue (that looks over all of Jumanji) and call out "Jumanji".

Along the way, the group begins to lose lives through various means when completing game levels. They are chased by Van Pelt's men, who is tracking their progress through the eyes of the animals in the jungle. Bethany teaches Martha to be a woman and to use her sexuality. While Fridge teaches Bethany to pee like a man. Using a map given by Nigel, and read by Bethany, the group reaches a town called Bazaar. The group is supposed to find the missing piece of the map at Bazaar. The group start working together to obtain the missing clue from a snake pit but are cornered by Van Pelt's men. They are rescued by Alex, the fifth player, whose avatar is a pilot named Jefferson "Seaplane" McDonough (Nick Jonas). Turns out Seaplane is the missing piece that the group was supposed to find.

Recuperating in a tree-house built by previous player Alan Parrish (protagonist of Jumanji), Alex thinks he has only been stuck in the game for a couple of months; everyone, including him, is shocked to realize he has been there for two decades. The newcomers vow to help him return home

They commandeer a helicopter (after Martha puts on a seductive show of dance fighting to distract Van Pelt's guards protecting the helicopter) and fly for the jaguar statue to return the jewel. Upon landing Alex loses his last life after a mosquito bites him, but Bethany performs CPR in time and transfers one of her lives to Alex in the process, saving him from dying.

Arriving at the statue, the players find themselves facing Van Pelt's forces and predatory guards. Using their resources and teamwork, the players distract the villains while Spencer returns the jewel to the statue and calls out the game's name. The game ends, disintegrating Van Pelt into many rats, and the players revert to their former selves and return to the real world but discover that Alex did not come with them. On their way home, they discover that the Vreeke household - once the neglected home of Alex's father "Old Man" Vreeke - has been restored. An adult Alex appears; he returned to 1996, and history was changed. He is now married and has named his eldest daughter after Bethany out of gratitude for saving his life.

Spencer and Fridge reconcile, Bethany becomes a better person and makes plans to go backpacking for another adventurous encounter, Martha starts dating Spencer, and the teens are now friends after their experiences in the game. The four hear Jumanji's drumbeats, but they take the game behind the school and destroy it with the bowling ball they found in detention to prevent anyone from playing it again.