The start of the movie flashes back to 1962 when Benny becomes Benny "the Jet" Rodriguez. The main part of the movie is set in 1972, ten years after the events of The Sandlot. A new crew of nine kids have moved into the neighborhood of San Fernando Valley in Los Angeles and have started playing baseball in the Sandlot. The previous kids have all grown up and moved away. Johnnie Smalls, the little brother of Scott Smalls, has heard the legend of "The Great Fear" owned by Mr. Mertle, who lives behind the Sandlot. A no-nonsense boy named David Durango the leader of the team, consisting of Tarquell, Mac, Saul and his little brother, Sammy, referred to as "Fingers", because he is deaf. Behind the Sandlot, next to Mr. Mertle's home, lives the Goodfairer family. David's rival, Hayley Goodfairer, the daughter and her two friends, Jenny and Penny, fight with the boys in a census to share the sandlot with Hayley calling David a little baby, and David calling Hayley a spoiled brat. The next day, David, Tarquell, Mac, Saul and Sammy, repeatedly demand Johnnie to tell the girls to leave the Sandlot, but they keep refusing. Johnnie then suggests that they share the sandlot. The others agree except David. Although since the girls are amazing at playing ball, he plans to make a deal with them; that they have to be on their team, they agree and they all become friends. On Friday afternoon, the kids play a game with a little league team. But when the team captain, Singleton, purposefully hits Hayley, David responds by punching Singleton in the face and forces him to leave, but not before telling him that the sandlot is theirs forever. Mac gets an aluminum baseball bat and hits the ball over the junk wall. The groups attempts to retrieve it but just as they are about to cross through a hole in the fence, Johnnie stops them and tells them the story of "The Great Fear": how it was born to bite and was different from its sibling puppies. There was a boy who loved the comic book hero named Rapid Rocket, and believed he ran as fast as him. On his first day of school, he went past the house belonging to Mr. Mertle, and The Great Fear got out and chased the boy. It was unknown what happened to him after he was cornered by "The Great Fear." Soon afterward, a wall made of assorted junk was built. Ever since, if anything went over the fence, nothing would ever come out. The main conflict comes when Johnnie accidentally launches a model Space Shuttle. The model was built by Hayley's father, a NASA engineer. It was said to be the future of NASA. Unfortunately, Mr. Goodfarier's rocket lands in Mr. Mertle's back yard. Hayley, along with everyone else, frantically attempts many ideas of getting it back, including hiring a selfish little boy called "The Retriever", but he fails, and decides to retire and go home. Then, just like Benny Rodriguez from the first movie, David decided to go over the wall himself to retrieve the rocket. Here it is revealed that the little boy who was bitten by "The Great Fear" in the story was David himself. He retrieves it and escapes the Great Fear's yard. The Sandlot kids soon discover that The Great Fear got loose. David then hops on his bike and rides out of the sandlot. The Great Fear then chases after David. David then goes through a construction site, and then David gets off his bike and runs back to the sandlot. David hops over the junk wall back to Mr. Mertle's yard and falls through the tunnel that Mac used to try to get the rocket back. The dog knocks over the wall and saves David from suffocating. When David defeats the dog, it's revealed that the dog's real name is Goliath; after that, the kids can be seen running to the sandlot because Goliath got away, and realize that he only wanted to get out to see his girlfriend dog, Tiny. As all the kids are leaving, Hayley and David share a kiss, and Mr. Mertle, tired of kids thinking he's grouchy, decides not to build a new fence.
