In those brief lines — nimbly delivered by Ellen DeGeneres as the blue tang Dory, introducing herself to Albert Brooks’ Marlin the clownfish in Finding Nemo over a dozen years ago — are a potent blend of daring wit, restless invention and creative ruthlessness typical of Pixar in its prime.

Dory’s perpetual forgetfulness was at once a stroke of comic genius, a flourish of poignant character development, a crucial plot point and — fleetingly evoked by the unresolved tension of that passing question, trailing off and quickly forgotten — a hint of quiet tragedy and darkness.

Set one year after Finding Nemo, Finding Dory introduces us to a nearsighted whale shark (Kaitlin Olson), a beluga whale (Ty Burrell) suffering from psychosomatic echolocation dysfunction and an octopus (Ed O’Neill) missing a tentacle (so he’s really a “septapus,” as Dory notes). Oh, and a wall-eyed, disheveled loon who easily imprints on anyone or anything that looks her in the eye and coos just so, and will thereafter do whatever you want.

Along with Nemo’s gimpy fin and Dory’s memory troubles — here unambiguously presented as a cognitive disability unique to Dory, neither a characteristic of her species nor, so far as we see, a family trait — Finding Dory is like a whole classroom of special-needs sea creatures.

Which I guess, given an important location, makes some amount of sense, though nothing much comes of any of it. With one key exception, these handicaps lead to no character insights, no key plot twists, no comic payoffs, no poignancy or darkness. The myopic whale shark bumps into things; the beluga frets about echolocating until he doesn’t; the octopus grumbles about his missing tentacle but otherwise manages astonishingly well, like American Ninja Warrior well.

The exception, of course, is Dory, whose memory issues become the focus of parental concerns for a child with special needs — partly in relation to anxious Marlin, but also, in elusive but increasingly vivid flashbacks, to Dory’s long-lost parents. This may not be as universal or well-realized a theme as Nemo’s helicopter-parent anxieties, but parents and children will both relate in their own ways.

Finding Dory is pleasant, amusing, modestly clever and occasionally moving, though it never approaches the emotional or creative heights of Finding Nemo, the greatest father-son story in Hollywood animation history and one of the best American cartoons ever made.

I smiled, laughed and shed a tear or two. A crucial moment in the third act turns on an image with a throat-lump-inducing emotional payoff that somewhat reminds me of the last line of Tie a Yellow Ribbon: an image that wordlessly speaks of extravagant love and steadfast hope against hope for reunion after years of separation.

Finding Dory combines two familiar sequel devices. First, it shifts the focus away from the original main characters and promotes a colorful comic-relief supporting character to the rank of protagonist (see Cars 2, Penguins of Madagascar, Minions, etc.).

Second, it continues a character’s trajectory by bringing her back to her roots, revealing new insights into her origins and specifically sending her on a quest to find her long-lost family (compare both Kung Fu Panda sequels, How to Train Your Dragon 2, Toy Story 2, etc.).

Dory’s search takes her clear across the Pacific from Australia’s Great Barrier Reef to the coast of California. This seems dubious, on a number of levels. Finding Nemo was hardly a nature documentary, needless to say, yet clownfish and blue tangs really are native to the warmer waters of the Indo-Pacific, including the Great Barrier Reef.

Marlin and Dory’s journey in Finding Nemo took them perhaps 2,000 miles along the Australian coast, which was obviously a stretch, but now these homebody fish cross more than 7,000 miles of open ocean — to a locale where Dory’s species is not native.

It’s also a less exotic setting. I appreciated Finding Nemo taking children to a region in which at least some characters had Australian accents (and Americans, in a disparaging throwaway gag, are the rather disreputable Other who “think they own the whole ocean”). Only last year Inside Out took us to San Francisco — and next year’s Cars 3 has been tied to California’s Route 99. Does the Golden State have a product-placement deal with Pixar, or is this just limited imagination?

I’m carping, I realize. Dory, Marlin and Nemo remain endearing characters (Hayden Rolence replaces now-22-year-old Alexander Gould as the voice of Nemo, who doesn’t seem to have aged at all in the year between the films); of the new cast, O’Neill’s Hank the octopus is a particular standout. Hank’s squash-and-stretch movements push computer animation to yet another high-water mark, and his mad skills are highly entertaining — so entertaining, in fact, that I kind of wish the movie had been about him.

Partly that’s because I can accept Hank’s extreme physical liberties more easily than that of Dory, Marlin and Nemo, who move about with far greater ease than in the comparatively, ah, grounded original.

Most of the story is set at the fictional Marine Life Institute, originally envisioned as a Sea World-like marine park, but reimagined as a rescue-and-rehabilitation marine center in the wake of the anti-Sea World exposé documentary Blackfish. Suffice to say, fish at the Marine Life Institute are a lot less contained than you’d expect them to be. On the other hand, Dory’s origins do make sense of her previously unexplained ability to read (and speak whale).

It’s fair to say that Finding Dory is probably Pixar’s best non-Toy Story sequel to date, which isn’t saying much. Monsters University was at best lazy Pixar lite, and Cars 2 might as well have been a mediocre DreamWorks effort.

As for Finding Dory, it’s basically the sort of sequel I would have expected Disney to produce without Pixar’s involvement, had Pixar gone its own way, as it flirted with doing a decade ago, instead of being bought by Disney. If in some alternate reality Disney and Pixar actually did separate, and a Disney sequel to Finding Nemo fell through a wormhole from that reality to ours, Finding Dory could easily be that sequel.

That doesn’t make Finding Dory a bad film, by any means. It just makes me wonder what sort of films the Pixar of that other reality is producing without Disney. Movies like Inside Out, perhaps. How long before another one of those falls through the wormhole?

Steven D. Greydanus is the Register’s film critic and creator of Decent Films.

He is a permanent deacon for the Archdiocese of Newark, New Jersey.

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