This article contains spoilers for “Jurassic World Rebirth.”

Plenty of filmmakers have been able to leave their unique stamp on all number of movie monsters, but few have held as much of a stronghold on a singular creature than Steven Spielberg with dinosaurs. 1993’s “Jurassic Park” built upon the previous incarnations of these prehistoric beasts in films like Harry O. Hoyt’s “The Lost World,” “King Kong” and “One Million Years B.C” by way of technological wizardry we’re still attempting to recapture. The mix of practical effects and innovative leaps in computer-generated imagery helped establish a world in which dinosaurs were these beautiful, terrifying, and, most importantly, tangible creatures. It was as if Stan Winston, Phil Tippett and the talented folks at ILM plucked these extinct forces of nature from out of time.

As far as Universal was concerned, they essentially held claim to the definitive screen dinosaurs that every one of its successors would be compared against. “Jurassic Park” probably should have been a one-off, but leaving that much money and potential on the table is too alluring to pass up. The best you could hope for in terms of sequel ideas is finding similar ways to highlight these magnificent dino creations against creative stories and characters. Each subsequent “Jurassic” installment shows how everyone seemed to have learned the wrong lessons from Spielberg’s seismic blockbuster.

Every “Jurassic” film finds itself more concerned with presenting a bigger, badder batch of prehistoric creatures that just about everything else gets lost in the shuffle. By the time we get to the “Jurassic World” rebrand, there’s this tired sentiment of people not being as interested in dinosaurs as they used to be. At this point, the “Jurassic” series is so far removed from the singular magic of Spielberg that it’s virtually unrecognizable. It’s a collection of monster movies now, and that’s fine. “Jurassic Park III” is the best sequel because it drops the pretense of trying to recapture the Spielberg magic of the original and commits to being a 90 minute creature feature.

Gareth Edward’s “Jurassic World Rebirth” finds itself in an interesting position where it wants to return to the simple thrills of the original film, while still luring general audiences in with a good hook. In this case, the dinosaurs on this island aren’t just more of the same, but rather, the rejects left behind by the now defunct InGen corporation. The previous “Jurassic World” movies, to some degree, have already shown us a glimpse of this practice with genetically altered hybrids like the Indominus Rex and the Indoraptor. In “Rebirth,” however, these aren’t just gene splices gone wrong, but mutant creations that are considered the worst of the worst. If the “Jurassic” series is going to keep lumbering on, they might as well get weird and freaky with the dinosaurs, but this latest entry somehow manages to fall flat on that front too.

“Rebirth” gets off to a promising, yet incredibly dumb start, as we learn that the nefarious InGen had taken hold of another island in Ile Saint-Hubert as yet another testing ground. The marketing flat-out lies by saying this is where the rejects for the original “Jurassic Park” were left behind. Given the timeline logistics, however, Site C is more so an experimental hub for the dinosaurs that would eventually get transferred to “Jurassic World.” The island is about to be visited by a group of black ops mercenaries led by Scarlett Johansson’s Zora on behalf of an pharmaceutical expedition to extract three blood samples that could lead to the eradication of heart disease.

In the opening of “Rebirth,” we’re introduced to the flagship mutant dinosaur that’s on all the posters with the Distortus rex. An evergreen moronic InGen scientist manages to screw up the island’s entire operation with the help of a Snickers wrapper that gets caught up in the machination, causing all operations to seal up. From behind the glass, it’s clear that the shrouded figure of the D-rex is beyond any “Jurassic” creature we’ve ever seen. This tease is clearly setting up the D-rex as the film’s big bad, but the dino only disappointingly returns to the fray with less than 15 minutes left to go.

Part of what makes “Rebirth” such a colossal disappointment is that it’s such an interminable slog of grab bag nostalgia baiting and underwhelming characters. You go for so long without the D-rex that by the time he does show back up, the excitement factor has been sucked out of the whole experience, making him just another obstacle to get through. Once we get to see what the D-rex looks like in its full glory, it’s little more than a Rancor grafted onto a T-rex body, which just isn’t enough of a sell on the “worst of the worst” angle.

There’s another mutant prospect called the Mutadon, which is a blend of a Pterosaur and a Velociraptor. Given how the previous “Jurassic World” movies neutered the fear factor with raptors, it makes sense that giving them the ability to fly sounds like a terrifying concept. Alas, the Mutadon is just as much of a disappointment, if not more so. You get glimpses of it throughout the back half of the film descending upon regular raptors sneaking up on their prey. But instead of imbuing them with their own personality, their big set piece is reduced to recreating the raptors in the kitchen set piece from “Jurassic Park,” but in an island 7-11 instead.

The issue with both of these mutants is that they’re not very scary or compelling movie monsters. It’s as if “Rebirth” is afraid to go full mad scientist and let these things be out-of-the-box abominations, let alone ones that actually pose any kind of credible threat to its ensemble. What’s even more disappointing is that they’re all overshadowed by the series’ most beloved creature with virtually no modification.

In the first two “Jurassic Park” movies, no dinosaur holds a crown to the T-rex, which strikes fear in the hearts of anyone who comes across her path. When we get to “Jurassic Park III,” however, she’s taken out by a ravenous Spinosaurus who swipes her crown within the first act in a welcome bit of subversion. The “Jurassic World” movies may come up with various hybrids to dethrone her, but by the end, mama T-rex establishes her dominance with ease. “Rebirth” was the perfect opportunity to make her look like a relic of the past with the arrival of the D-rex and various other mutants, yet the film’s most effective sequence is with the Queen of the dinosaurs.

“Rebirth” makes an admirable attempt to recreate the raft sequence from Michael Crichton’s original “Jurassic Park” novel, and it’s the most impressive set piece because the stranded Delgado family have to quietly evade the titan before she wakes up. The film version sees the T-rex emerge from her slumber and chase this family down a series of rapids, with the scariest moment being young Isabella (Audrina Miranda) trapped underneath it while those jaws threaten to gobble her up. I actually thought this was actually going to let a kid die in one of these, then remembered it was a “Jurassic World” movie. Even so, this entire sequence calls into question the need to keep remaking more “dangerous” dinosaurs when the OG still holds all of her terrifying potency.

The closest “Rebirth” ever comes to a mutant dinosaur that actually inspires some sort of awe is with the Titanosaurus and their long and swift tails, even if they’re only present in the scene that’s blatantly ripped from the ’93 film. Edwards seemed like a natural fit for the “Jurassic” series, given how well he managed to convey a grand sense of scope with 2014’s “Godzilla.” But “Rebirth” contains very little of his strongest attributes as a filmmaker.

“Jurassic World Rebirth” is now playing in theaters nationwide.