We first met memory-challenged blue tang fish Dory in “Finding Nemo,” Pixar’s runaway hit released in 2003. The original film centered around Nemo, an adorable young clownfish captured by men making their living by finding tropical fish for home aquariums. Made 13 years later, but set just one year after the original, Dory (voiced by Ellen DeGeneres) gets a bump on the head resulting in new, and only sporadic memories from her early life. The revelation is that Dory was the much-loved hatchling of Jenny (Diane Keaton) and Charlie (Eugene Levy).

When little Dory became lost, she found herself asking every creature she met, “Can you help me? I’m looking for someone.” Mostly funny, but with a tinge of sadness, bubble-eyed Dory can’t remember who or what she’s looking for. Eventually she meets Nemo (Hayden Rolence) and his worrywart, single dad Marlin (Albert Brooks), who treat her like one of the family and do their best to overlook Dory’s chaotic behavior.

After remembering her parents, Dory gets a lead on their California aquarium location, and she pleads with Marlin and Nemo to accompany her across the ocean to find them. It’s a good thing massive sea turtle Crush (again voiced by director Andrew Stanton) is on hand to take the trio there via a fast moving ocean current.

Predictably, Dory winds up losing Marlin and Nemo, but well-intentioned researchers bring the lost fish to the rehab and release center, also inhabited by her parents. At first Dory languishes in quarantine, but soon she’s approached by clever, somewhat crotchety octopus Hank (Ed O’Neill). He wants Dory’s ticket to the Cleveland aquarium, and agrees to help Dory find her parents in exchange for it.

The film “Finding Dory,” ought to be called “Finding Hank,” because its most amusing passages depict Hank camouflaging himself to blend in with walls, paintings, or industrial piping, to evade his would-be captors who seem almost bored when informing one another “The octopus has escaped — again.”

While Dory and Hank attempt to make their way through the labyrinth aquarium (undetected by humans), back outside the institute Marlin and Nemo seek to enter the facility with the aid of lazy sea lions Rudder (Dominic West) and Fluke (Idris Elba). Getting inside requires Marlin and Nemo to jump into a tiny bucket filled with seawater, putting their faith in the wild-eyed loon who has agreed to give them a lift.

Throughout the film, DeGeneres hits the right notes with her vocal performance, excepting her efforts to speak “whale” by adding oddly pitched “oooos” to the dialog.

Director Stanton, who also cowrote, once again proves his casting brilliance (other aquarium animals include a beluga whale and whale shark voiced by Ty Burrell and Kaitlin Olson), along with an ability to create credible underwater locations, and entertaining action set pieces. Dory, Hank, Marlin and Nemo, all have interesting adventures, but just as Dory stood out in “Finding Nemo,” it’s Hank we crave more from in “Finding Dory.” Since Hank can be very difficult to see when camouflaged, if there’s a threequel then “Finding Hank,” should be half the film’s fun — at the very least.