Not every sequel (or prequel) works. Perhaps that’s one of the reasons why director Dan Scanlon and his colleagues at Pixar put so much effort into “Monsters University, to validate its existence. It’s that love for animated films, along with creativity and seemingly boundless imagination, that makes this prequel so good. The movie’s strongest asset is definitely its familiar stars. It’s great to spend quality time once again with Mike (Billy Crystal, never better) and Sulley (John Goodman, as awesome as always), who have to make it through freshman year at Monsters University. They both want to become Scarers. It’s easy for Sulley, who has the look of a frightening creature and whose father was a famous Scarer. For Mike, things don’t go as planned, and therein lies the tale, which I will not spoil. Director Dan Scanlon certainly keeps the fun coming, but it’s the Pixar animators who keep grown-ups as riveted as the kids with visual marvels that delight. They also understand that for a movie to have resonance it can’t be built on a foundation of a single joke. That’s why they pepper their film with plenty of laughs and more important, they make us care about these characters as if they were real. I think they can be proud of what they’ve achieved here, and I know that audiences of all ages will be grateful.