Andy's class is going on a field trip to the science museum, so his mom gives him spending money for the gift shop. When Woody the cowboy, Buzz Lightyear the space ranger, and Rex the dinosaur hear this, they panic! What if Andy picks a toy that he likes more than his old toys? Woody, Buzz, and Rex have a plan: they will stow away in Andy's backpack and make sure Andy chooses a good toy from the gift shop. But when the toys are separated from Andy at the museum, will they still be able to stop him from buying the wrong toy?