In Pixar's hands, the ocean — equal parts danger and wonder — is a vast metaphor for the choppy waters of parenting.

Cloistered coral reefs of home are surrounded by frightful drop-offs and strong currents that can sweep a little fish out to an immense sea.

When the difference between survival and shark bait is flipper-thin, how much line do parents give before reeling in?

"Finding Dory," a sequel to 2003's "Finding Nemo," shifts the tale from Nemo, the clownfish with a weak fin, to Dory, the blue tang with short term memory loss — or as the baby Dory seen early in the film says, "remembery loss."

The adventures of both Dory and Nemo are born out of straying too far from anxious parents. The gulf of separation stretches wider and longer in "Finding Dory," but it's covered the same way: by pluckily overcoming genetic handicaps and trusting in the Pacific-sized love of family.

In the Pixar brood, the sweetly sentimental "Finding" movies are the most ready-made for parent-kid bonding; they would surely inspire countless father-son fishing trips if that didn't mean hooking the movies' heroes.

"Finding Dory" promotes the original's daffy supporting character (so perfectly voiced by Ellen DeGeneres) to protagonist. But it's not a simple switch in perspective: In seeing through her forgetful fisheyes, you realize how terrifyingly disorienting it is to be Dory. "Finding Dory" is "Memento" under the sea, with a much more chipper lead forever at pains to remember why and where she's going.

The film, directed by Andrew Stanton, picks up six months after "Finding Nemo." Dory is living with Nemo (Hayden Rolence, replacing Alexander Gould) and Marlin (Albert Brooks), but she's nagged by flickers of memory of her family.

A flashback of Dory's childhood follows. Though it doesn't reach the gentle poetry of the famous montage in "Up," it movingly reveals Dory's origins: a challenged fish whose parents (Eugene Levy and Diane Keaton) teach her mantras for coping ("Just keep swimming") but are helpless when a current sucks her away. Dory grows up a lost and confused orphan.

Energized by clues of remembrance, Dory, Nemo and a reluctant Marlin travel from Australia to California, where her search leads to the Marine Life Institute.

So much of the dazzle of "Finding Nemo" was the colorful richness of its aquatic life: sharks in recovery, pelicans interested in dentistry, Willem Dafoe's battle-scarred striped fish. So why, with oceans to explore, does "Finding Dory" cling so closely to the shore?

The trip across the Pacific goes in a flash. The action takes place almost entirely jumping between tanks at the institute (subbed in by Pixar for an originally planned SeaWorld-like location) and in a number of less exotic (and less creative) scampers on land.

The sidekick here is a sullen seven-legged octopus named Hank (Ed O'Neill), who helps Dory navigate the complex to facilitate his own escape. But the movie's high point unquestionably belongs to the pair of British sea lions (Idris Elba and Dominic West, "Wire" veterans reunited) who bark at any creature that dares approach their sunning rock.

"Finding Dory," bright and clever like most all Pixar releases, has the animation studio's familiar blend of wit, heart and visual detail. But it's missing its own magic. Like Dory's questions, it feels a bit like a repeat. It's certainly no "Cars 2" (Pixar's low point) but neither does it approach the glory of "Toy Story 2."

Pleasant as it is, if "Finding Dory" feels a little disappointing, it's partly because the appetizer upstages the main course. "Piper," Alan Barillaro's six-minute short that precedes the film, is about a baby sandpiper learning to feed, scampering in an out of the surf. The photorealistic imagery may be the best yet for Pixar. In the 13 years from "Finding Nemo" to last year's clunky but gorgeously animated "The Good Dinosaur," Pixar — all the while making us tear up — has effectively mastered water.

"Finding Dory," a Walt Disney Pictures release, is rated PG by the Motion Picture Association of America for "mild thematic elements." Running time: 97 minutes. Three stars out of four.

-AP