Alan Parrish (played by Robin Williams) finds a board game (Jumanji) and decides to play it with a friend Sarah Whittle without really knowing what it was. Very soon unexpected things happen and without warning Alan disappears into thin air and Sarah is chased out of the house by scary looking bats. 26 years later, two other kids in the same house (Judy Shepherd played by Kirsten Dunst and her brother Peter played by Bradley Pierce) play the same game after they find it in the attic while their aunt is not home (their parents died in an accident).
They are able to return Alan Parrish to a normal life after he disappeared into the game and in order to finish the game, they also track down Sarah Whittle but in order for everything to return to normal, they must play till the end. It ain't easy on anyone, including people not playing the game. Life in this tiny town is turned upside down and wild animals are roaming on Main Street.
It is an excellent fantasy/action moview and perfect for not only kids but even adults who like fantasy and action - for example, Pirate of the Caribbean Dead Men's Chest. Unfortunately parts of it border on horror (in a fun way, though, and nothing like the violence and horror you see in video games) but still strongly recommended.