"Finding Dory" is a Pixar movie, featuring the return of some of Pixar’s most beloved characters, but there’s something very un-Pixar about the splashy summer sequel – mainly that last word: sequel.

Sequels are not why we love Pixar, why that name, like Marvel for many, has become seemingly a genre of its own and a deeply trusted one at that. Yes, "Toy Story 2" and "Toy Story 3" were great, wonderful movies, but those are exceptions to the rule. Sequels, the rest of the time, are where the influential animation studio trades out its signature deep imagination and even deeper emotional depths and instead behaves like its animation imitators, where it cashes in on being "Pixar" rather than actually being Pixar. It’s where the studio acts like the student who scored straight As, nabbed 4.0s and took all AP classes in high school only to go to college and take basic level courses freshman year. It’s going for the easy A.

As disappointing as that can feel, though, an easy A is still an A. And in the same way, "Finding Dory" is still a fun lap through friendly waters – even if those familiar waters feel just a few drops shallower this time around.

It’s been 13 years since the first film, but apparently in fish years, it’s just been a year since Marlin (Albert Brooks) and Dory (Ellen DeGeneres) teamed up and took to the open ocean to find little Nemo. This time around, however, it’s short-term memory loss-stricken Dory that’s the cause for adventure, as she begins to experience sporadic flashbacks to her childhood, back when she was a fish toddler made up of about 80 percent eyeballs and about 1,000 percent the cutest thing you’ll ever see in your life.

Even more important than the living embodiment of adorable, however, Dory begins to remember her long-lost parents (Eugene Levy and Diane Keaton) and her old home: a California aquarium and fish hospital. Thus, the finned friends take off for the West Coast, running into old friends and requiring some new ones – namely a cranky Cleveland-dreaming octopus, voiced by Ed O’Neill, and two bickering whales in recovery – to find where Dory once called home.

Unlike most Hollywood sequels and reboots, "Finding Dory" smartly focuses more on the new rather than the old, saving its familiar faces mostly for quick cute cameos and happily creating new memorable characters full of laughs and heart – three hearts in the case of Dory’s octopus pal Hank, a worthy co-pilot for this aquatic adventure. As voiced by O’Neill, there’s a fun snap to his irritated banter with the forgetful Dory yet also a heart-heavy weariness and sincerity in his voice that adds more emotion than expected. An incident that rendered him actually a septopus, for instance, is never defined, but thanks to his nuanced voice work, it quietly hangs over him and his quest for Cleveland-based isolation and hits harder than it would simply on the page.

Meanwhile, the animators – who, as always from Pixar (even in lesser material like the "Cars" films), create a gorgeous, visually impressive world of color and beauty that feels rich with life and texture leagues-deep into and outside the frame – have a field day working with this new piece of tentacled comedic clay, finding fun and clever ways to make him a nimble master of disguise throughout the aquarium.

The rest of the cast provides a lot of fun as well, from Dory’s duo of whale friends (voiced by O’Neill’s "Modern Family" co-star Ty Burrell and Kaitlin Olson of "It’s Always Sunny in Philadelphia") to a pair of lazy sea lions, voiced by none other than McNulty and Stringer from "The Wire," and their bug-eyed bird pal Becky.

Together, they add up to perhaps one of Pixar’s overtly silliest movies – especially when it gets to the frantic big finale, featuring fish driving trucks through roundabouts, a double "Free Willy" moment and a sea otter cuddlefest. Even an extended sequence involving an octopus speeding a baby stroller around an aquarium unnoticed can’t prepare the audience for that level of reality-breaking zaniness. Luckily, returning director Andrew Stanton and the rest of the Pixar crew keeps it just on the right side of ridiculous and peppers the final act, as well as the rest of the movie, with enough funny gags and creative visual jokes to make it a lot of giggly fun and worth the weird tonal collision. Even just the mere disembodied voice and presence of Sigourney Weaver ends up being a great running laugh.

All of those gags, however, can’t completely hide the faults in "Finding Dory," namely that this story and its emotional beats feel very familiar – something you rarely can say for a Pixar project. Like Dory swimming past some kelp and shells, there’s a feeling of déjà vu that makes the whole thing feel a lot shallower and slighter than before, that it's a nice addition if not all that necessary.

Add in a slow start that takes a while to build momentum (there’s a lot of recapping and half-baked adventuring) and the odd tonal meshing – it may seem goofy to say there’s a big difference between a talking animal movie and a talking animal movie in which an octopus hijacks a truck, but there is – and it just feels less consequential, like a cover of a favorite song rather than either the actual song or a new song.

Even so, Pixar’s big emotional beats, however familiar, still hit their marks and go beyond the typical family movie messaging. Leave it to Pixar that even one of its lesser efforts has more than the usual to say, hitting rather touching notes about a whole cast of characters with disabilities – not just Dory; Hank has lost a tentacle, while one whale is near-sighted and the other is concussed – learning about accepting oneself and finding one’s way with a disability rather than in spite of it. The movie starts with Dory muttering, "Don’t be such a Dory, Dory," but by the end, that Dory-ness is to be loved and appreciated.

It may seem unfair to talk about a movie that hits on these kind of nuanced, thoughtful themes and lessons – while still working as charming, fun entertainment – as a slight disappointment, but thus is the curse of being Pixar. The company built its reputation on raising the bar, so it’s hard to accept when it decides to tread water instead. And sadly, that’s becoming the new normal. Of the next four Pixar movies, there’s only one original film mixed into the bunch. The rest are sequels – though at least there’s a bit of comfort in knowing that while that’s not what they do best, as "Finding Dory" shows, they at least do it better than most.

Lastly: The pre-movie short, "Piper," is slight but charmingly sweet, adorably precious and gorgeously animated. So yes, it’s basically the short version of "Finding Dory."