There was a time, not too many years ago, when the arrival of a new Pixar release was cause for excitement—not just because chances are it would be good, but because it was a true movie lover's thrill to find out what fresh and innovative premise the studio had cooked up next. Then came a parade of sequels. 2010's "Toy Story 3" was acceptable because it felt like an organic continuation and conclusion of the story (never mind that a truly unnecessary "Toy Story 4" is already in the pipeline). More offensive was 2011's appalling "Cars 2," a hatefully desperate money-grab that turned its back on every last message 2006's lovely "Cars" stood for. With even more sequels in Disney and Pixar's immediate future (including the upcoming spin-off "Planes" and "Finding Nemo" follow-up "Finding Dory"), we now arrive at "Monsters University," the prequel (how's that for sounding new and exciting?) to 2001's charming "Monsters, Inc." The best way to approach any movie is with few expectations or pre-conceived notions, and that's because, as is the case with "Monsters University," sometimes said film can genuinely surprise. This is Pixar's most assured and even original picture in years, deeper and more soulful than its predecessor as it traces the beginning of the friendship between monsters Mike Wazowski (voiced by Billy Crystal) and James "Sulley" Sullivan (John Goodman) and informs how both of them became professional scarers in the land of Monstropolis.

As far back as he can remember, diminutive cyclops Mike Wazowski has dreamed of becoming a scarer in the bedrooms of human children everywhere, powering his world's energy with their terrified screams. Though he faces the hurdle of being a rather affable fellow, he has lofty dreams as he enters Monsters University as a freshman in the so-called "Scaring School." It is here that Mike first meets James "Sulley" Sullivan, a larger, more typically scary classmate whose famed family lineage within the program comes with an off-the-charts ego. To both of their disappointments, their sparring gets them kicked out of the Scaring School during their final exam by stern crustaceous dean Abigail Hardscrabble (Helen Mirren). Not about to give up his dreams, Mike joins outcast fraternity Oozma Kappa and signs them up for the annual Scare Games competition. With nowhere else to turn, Sulley also joins the team, leading Dean Hardscrabble to pose an ultimatum: if they win, the whole group will be welcomed into the Scaring School. If they lose, they'll have to leave the college for good.

The cheery, auspicious feature debut of writer-director Dan Scanlon (co-written by Robert L. Baird and Daniel Gerson), "Monsters University" is packed to the gills with clever asides and even cleverer in-jokes, many of them playing on the tried-and-true conventions of college and fraternity comedies. Like a cross between "Revenge of the Nerds" and "The House Bunny"—only with giant-tentacled librarians and students who look like aliens and colorfully deformed grizzly bears—the film is fast-paced and humorous in different ways for children and grown-ups. Little details, such as the Oozma Kappa initiation trying to be threatening and mysterious while the chirpy Ms. Squibbles (Julia Sweeney), mother of frat member Squishy (Peter Sohn), does her laundry on the other side of the basement, are very funny. Also a riot is Ms. Squibble's choice of music; let's just say it's not adult contemporary. Meanwhile, the central Scare Games, which run the gamut from races in the dark as the contestants dodge poisonous, glowing urchins, to a "Don't Scare the Teenager" maze, are entertaining and varied, like a goofier TriWizard Tournament from 2005's "Harry Potter and the Goblet of Fire."

As the Oozma Kappas begin to succeed, rising ever higher on the leaderboard, it may seem exceedingly predictable where things are headed. After all, in "Monsters, Inc.," Mike and Sulley were already seasoned scarers, so it is a given that they somehow succeed. Where most viewers will be wrong is in how they get there, which isn't nearly as easy as winning a competition. The film's last act might have done well with a more judicious editor—at 103 minutes, it is eleven minutes longer than "Monsters, Inc."—but it also paves the way for a deepening bond between Mike and Sulley, who start off as adversaries yet find common ground in their various insecurities and hopes for their futures. There is a shared respect that develops in these two kind-hearted guys that brings an added levity to the plot's progression and gives this movie the edge over its precursor.

It will be nice to see Pixar eventually return to taking chances with a wholly original concept rather than piggybacking on a proven property that already has a built-in audience, but "Monsters University" proves that there is still imagination to be had and further territory to sometimes explore with pre-established characters. As Mike and Sulley, the perfectly winning Billy Crystal (2012's "Parental Guidance") delights in growing beyond the "comic relief" character, while John Goodman (2013's "The Hangover Part III") voices Sulley as a more immature version of the honorable monster/man he eventually becomes. The vocal highlight, though, is Helen Mirren's (2012's "Hitchcock") tastily stiff-necked reading of Dean Hardscrabble, whose idea of words of encouragement on the first day of class are, "If you're not scary, what kind of monster are you?" The only way the role could have been any better is if she had been named Mrs. Tingle (a reference to her similarly domineering role in 1999's "Teaching Mrs. Tingle"). Lovingly animated, paying careful attention to details such as the passing of seasons while having particular fun with a nighttime summer camp setting in the climax, "Monsters University" is, so far, this summer's animated family film to beat. Welcome back, Pixar. You've been missed.