Steven Spielberg returns to executive produce the long-awaited next installment of his groundbreaking "Jurassic Park" series, "Jurassic World." Colin Trevorrow directs the epic action-adventure from a screenplay he wrote with Derek Connolly. (Universal Pictures)

‘Jurassic World,” the third sequel to 1993’s classic fantasy-adventure “Jurassic Park,” gets off to an imaginative start. After an opening sequence of clawed, amber-eyed creatures poking through crackling egg shells, we see an entire taloned leg stomp down, only to have the camera reveal that it belongs to a common bird. Moments later, a bickering mom and dad are sending their two sons to visit their aunt Claire, who oversees the operations of Jurassic World, a luxury resort and theme park that has been in operation for more than a decade, inviting visitors to get up close and personal with triceratopses, T. rexes, Apatosauri, pterodactyls and other genetically resuscitated prehistoric creatures. “Remember, if something chases you, run!” the boys’ mother laughs, sending them off.

Sure, it’s all lighthearted foreshadowing until the first fat security guard gets chomped, which happens in due course in “Jurassic World,” a super-size, self-referential, drastically uneven addition to the Steven Spielberg franchise. When the kids finally get to Isla Nublar, the younger, dino-obsessed Gray (Ty Simpkins) is dazzled; Zach (Nick Robinson) can barely tear himself away from his cellphone. Once at the sprawling, self-contained theme resort, they are put in the care of a similarly multi-tasking administrative aide, who leads them with casual indifference past sights that would have taken her breath away just 14 years ago, when the most recent “Jurassic Park” sequel came out. (This movie, however, takes place in a world where the two intervening movies do not exist.)

Aunt Claire — played by Bryce Dallas Howard — is just as blasé: She only cares about increasing attendance numbers. “No one’s impressed by a dinosaur anymore,” she explains to potential corporate sponsors at one point. “Consumers want them bigger, louder — more teeth.”

Of course, this is a meta-commentary on the movie industry itself, and a clever way to manage audience expectations. We’re going to give it to you, the filmmakers seem to be saying, but don’t blame us if it all goes kerblooey in a nonsensical, hyperbolic Grand Guignol of CGI mayhem and overkill. Which “Jurassic World” does, but not before it engages in some cursory character development and promiscuous product placement, which ranges from conspicuous shots of Coke bottles and Imax insignias to a faintly amusing cameo from Jimmy Fallon.

The main attraction in “Jurassic World,” which was co-written and directed by Sundance discovery Colin Trevorrow, is the Dr. Moreau-vian creature that the park’s scientists have cooked up to “up the wow factor” with visitors, a massive albino hybrid called Indominus rex that is so potentially lethal that they’ve kept her in a paddock all her own. When things go awry, career-gal Claire’s corporate savvy can’t help her, nor can the philosophical pronouncements of the park’s billionaire owner (Irrfan Khan). The only man for the job is a rumpled, dimpled animal behaviorist named Owen, who has been working with a team of voracious Velociraptors to see if they can be trained. Surrounded by unethical dumbbells who either want to domesticate dinosaurs or commodify or weaponize them, Owen is the only one who seeks to understand them.

The dynamic between the earthy, authentic Owen and the brittle, dumb-bunny Claire is meant to harken back to such vintage romantic adventures as “Romancing the Stone” and the Indiana Jones movies. But way too much gets lost in translation here: The dim, selfish Claire is as charmless as she is clueless, and her scenes — in which she gets progressively more tousled and scantily attired — are a painful pastiche of sexist tropes. As Owen, Chris Pratt focuses more on smoldering and looking earnest than calling on the witty persona from “Guardians of the Galaxy,” a big waste of his natural gifts. The most enjoyable moments of an otherwise oddly joyless film actually belong to Jake Johnson and Lauren Lapkus, who steal the show in an especially amusing scene during a panicked evacuation.

The set pieces, admittedly, are impressive, especially when the benighted Indominus stomps her way to freedom, crushing, impaling and of course eating everything in her path (except the stars, natch). Later, Trevorrow stages a large-scale homage to Alfred Hitchcock when the park is attacked by swarming pterodactyls. In one of “Jurassic World’s” several references to its own DNA, Zach and Gray stumble upon the vine-encrusted SUVs and dusty equipment of John Hammond’s doomed park from way back in ’93, a nod toward Hollywood’s constant self-cannibalization and reflexive need to build bigger, more spectacular edifices on the crumbling ruins of its own past.

Anyone who knows about the role of Darwinian ethics and hubris in the Jurassic canon will understand why ambition doesn’t come in particularly handy in “Jurassic World.” Nor do the killer instincts of Owen’s raptors — once the villains of the piece, now poised for their moment of redemption. The promised bigness, loudness and “more teeth” finally arrive during the film’s chaotic final half hour, when a dilemma is resolved by what can only be described as a dino ex machina, Howard goes from Kathleen Turner into full Fay Wray, and the viewer’s only recourse is to brace oneself and try to process the ever-escalating, utterly nonsensical madness and mayhem.

As has been previously observed, every action movie today ends up as “Transformers” and, even when it’s cloned creatures fighting, the same is true here (with an antic dash of “Sharknado” tossed in for good measure). It’s not ambition or technical know-how or even plucky resourcefulness that save the day in “Jurassic World,” it’s good old-fashioned anthropomorphism. Humans, it seems, never learn. But if we did, where would sequels come from?

PG-13. At area theaters. Contains intense sequences of science fiction violence and peril, and brief profanity. 124 minutes.