About two-thirds of the way through Finding Nemo, a father sitting next to me cradled his crying young son and hushed, “Remember, pal: It’s only a cartoon.” The eye-popping derring-do that had the wee one wailing is perhaps the most astounding visual achievement the beautiful, CGI-wielding eggheads at Pixar have created in their five-flick history: a maw-of-the-beast POV inside a boisterous blue whale. As the movie’s teeny fish heroes desperately try to escape, the leviathan’s enormous muscled tongue lashes about in the dark, stormy space. It’s a set piece of such detail-rich digital wizardry that more than a few grown-ups were squirming as well. As the kid kept bawling, I grinned and thought, Those eggheads are getting a little too good.

Finding Nemo will no doubt be your favorite movie of the summer—but only if you’ve outgrown Bob the Builder. Although it’s just as funny and heart-tugging as such other Pixar gems as the Toy Story series, A Bug’s Life, and Monsters, Inc., this all-out charmer—about a widowed clownfish, Marlin (Albert Brooks), searching the Great Barrier Reef for his human-snatched son, Nemo (Alexander Gould)—is loaded with so many scary scenes that Junior may never want to go back to Ocean City. Pants-wetting moments include a death-defying sprint through a jellyfish field, a theater-dark descent into an abyss patrolled by a fang-bearing anglerfish, and a truly terrifying encounter with a “vegetarian” great white shark named Bruce (Barry “Dame Edna” Humphries), whose cartoon eyes turn black once he smells fish blood. (“Heeere’s Brucey!” he growls upon carnivorous relapse, chasing the good guys through a sunken submarine.)

For those of us out of Pull-Ups, however, Finding Nemo is mesmerizing. It opens with a rather Bambi-esque preface: In a quick-strike attack, a barracuda gobbles up Marlin’s wife, Coral (Elizabeth Perkins), and all of his children—except one. The lone survivor, Nemo, is born with a “lucky fin” (yeah, he’s got a gimpy flipper, so get your Kleenex ready), but that handicap doesn’t stop the lil’ clownfish from growing up to be cocky and curious, causing his sea-fearing father great anguish. “I promise I will never let anything happen to you,” Marlin says to his boy—and that means never letting Nemo out of his sight.

Until, begrudgingly, his son’s first day of preschool. Nemo, after being teased about his deformity, takes a dare from his pals (including an adorable octopus who is ashamed when she “inks” in public) to swim out into the perilous “Drop-off” and touch a boat. Inevitably, when he does so, Nemo is scooped up in a net and brought to Sydney, where he winds up fish-tanked in a dentist’s office.

Thus begin the dueling plot lines: For Marlin, the quest is to find his son on the basis of one clue—a scuba diver’s mask that falls to the ocean floor and has some curious scribbling on it. For Nemo, the quest is to escape his glass prison before he becomes a birthday present for the doc’s demonic niece, the brutal, braces-tortured Darla. (Psycho music shrieks every time she smiles.) Of course, there are some nice lessons about trust and friendship and resilience neatly tucked in among the action.

Once again, Pixar makes some curious but ultimately clever choices regarding vocal talent. I mean, who would have thought supreme weenie Billy Crystal would be so great as Monsters, Inc.’s one-eyed Mike Wazowski? The best surprise here is Ellen DeGeneres as Dory, a misfit regal tang fish with short-term memory loss—but the ability to “read human.” The comedian’s nonstop jabbering is a perfect fit for the lovable but lunkheaded sidekick, who buddies up to Marlin despite his pleas to be left alone. Brooks and DeGeneres display true comedic chemistry (and it helps that neither has had such great one-liners to zing in ages). Equally superb is Willem Dafoe, who gives Gill—the bitter, scarred ruler of Nemo’s new home—equal parts gravelly menace and sweet sorrow. Other star turns are provided by The West Wing’s Allison Janney, as an imprisoned starfish who gives play-by-play analysis of both the dentist’s periodontal procedures and his bathroom habits, and Geoffrey Rush, as a noble pelican who fights off a flock of single-minded sea gulls (they know one word: “Mine! Mine! Mine!”) to fly Marlin and Dory from the water to one yowza of a finale.

Pixar is unrivaled when it comes to entertaining kids and adults at the same time, and Finding Nemo raises the bar even higher. For adults, the in-jokes are plenty—Bruce is the name Steven Spielberg gave the mechanical shark in Jaws—and the topical gags always hit the target: After Nemo is captured, one fish harrumphs, “Humans think they own everything. Probably American.” Plus, the lobsters speak with Boston accents, Marlin claims he’s “H2O-intolerant,” and a school of moonfish do impressions, including one of the Sydney Opera House. (And make sure to stick around for the credits, where some old friends from other movies make cute cameos.) As the big folks chuckle at the wink-wink stuff, the kids who aren’t absolutely petrified will no doubt dig the surfer-dude sea turtle, Crush (director Andrew Stanton), and his bug-eyed son, Squirt (Nicholas Bird), who take Marlin and Dory on a whiz-bang ride along the East Australian Current—which looks very much like an underwater roller coaster, complete with a slow, ominous lift-hill and a belly-flopping lunge.

Oh, there’s goodness in virtually every frame. The movie’s palette of softly muted colors is flat-out gorgeous, especially when it comes to Marlin’s coral-reef home, where the filmmakers give you so much to look at that you’ll just have to come back again. And perhaps the finest computerized trick here—besides that whale of a tongue—is the seamless fluidity of the critters’ constant movement. As Nemo & Co. swim and sway in the ebb and flow of invisible currents, the movie can become hypnotic—which is why those fantastic action scenes are all the more jarring. Yeah, Finding Nemo is only a cartoon—but it’s also one of the best you’ll ever see. CP