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I was a huge Teenage Mutant Ninja Turtles fan when I was a kid. I watched the TV show religiously, I got the toys, and the 1990 live-action movie was the first film I ever saw in theaters. I didn’t see the 2014 reboot, mainly because it looked like producer Michael Bay had done exactly what he did to Transformers: taken a beloved children’s cartoon and transformed it into a joyless, bloated, gaudy, cheaply violent, and morally obtuse monstrosity.

The sequel to the reboot, Teenage Mutant Ninja Turtles: Out of the Shadows, suggests I might have to revisit that decision.

I’m not sure I’d go so far as to call it “good,” exactly. But then, looking back on the 1990 movie, it wasn’t exactly “good,” either. It was exactly what it should have been: a children’s Saturday morning cartoon, stretched just long enough for cinematic running time, but with real people. And people in turtle costumes.

Change the costumes to CGI, and you’ve basically got the new movie.

For the uninitiated, the four titular characters are Michelangelo, Donatello, Leonardo and Raphael (voiced by Noel Fisher, Jeremy Howard, Pete Ploszek and Alan Ritchson, respectively). They were created when four everyday turtles encountered a vial of radioactive sludge, turning them into four intelligent, walking, talking, pizza-loving teenagers. And yes, they’ve been trained as ninjas by Splinter (Tony Shalhoub), a rat also transformed by the ooze into a wizened old sensei.

They live in an elaborate lair in the sewers under Manhattan, and last time they defended the city from the supervillain Shredder, making friends with reporter April O’Neil (Megan Fox) along the way.

The plot of Out of the Shadows is gloriously stupid. The four turtles are hanging out in the rafters of Madison Square Garden, watching the Knicks, when Donatello gets a call from April: She’s on the trail of Baxter Stockman (Tyler Perry), a scientist working with the Foot Clan — Shredder’s personal ninja army. The Foot is planning to hit the police caravan carrying Shredder (Brian Tee) to a new prison and bust him out. So the turtles drive off in a tricked-out garbage truck to stop them.

Following a battle on the highway, Stockman uses some strange technology to teleport Shredder out of harms way. But the teleportation goes awry, sending Shredder into an alternate dimension. There he meets Krang (voiced by Brad Garrett), a foul-tempered talking brain with tentacles, who gets around via a robotic suit and has seemingly endless supplies of god-like technology. Krang offers Shredder a deal: Find the other pieces to the transporter, and Krang can bring his war machine — the Technodrome — to Earth, which they will then promptly conquer.

The rest of the film is the turtles chasing Shredder around the world as he tracks down the pieces, and then dealing with Krang’s arrival.

I say this is “gloriously stupid” sincerely, and with admiration. The script by Josh Appelbaum and André Nemec — who also penned the 2014 movie — is completely absurd, but proceeds with the kind of jaunty confidence and instinctive logic of the best kids’ cartoons. As director, Dave Green gets a bit lost in the computer-generated imagery, but he manages to keep enough of a handle on things to make some delightful visual sequences.

Besides Krang, a few other shoutouts from the original comic and cartoon are Casey Jones (Stephen Amell) — a disgraced cop who joins the turtles in crime fighting — as well as Bebop and Rocksteady (Gary Anthony Williams and Stephen Farrelly) — Shredder’s mutant henchmen. Will Arnett also shows up to deliver some comic relief. Laura Linney proves she is the world’s best sport by playing the film’s straight man — New York City’s chief of police — and totally nailing the part.

I can’t help but think the film’s one big problem is Michael Bay. There’s a weird disjunction between the comic book spirit that keeps trying to break through the film, and the macho brutalism that Bay mistakes for having a good time. The grungy detail of the film can feel oppressive, and Splinter and Krang fall flat because the filmmakers can’t quite hit the nuanced notes — Splinter’s quiet dignity, Krang’s perpetual outrage — to make the characters stick. And of course there’s one ridiculous sequence where Fox gets treated as a sex object.

That said, the film is surprisingly subtle with the turtles themselves. Being CGI, they don’t always feel entirely grounded. But each turtle has a distinct physicality, voice, face, and personality — Donatello is the genius, Raphael is the hothead, Michelangelo is the jokester, and Leonardo is the troubled leader. In the hyper-cut onslaught off a movie trailer, the turtles might blur together. But spend two minutes in a coherent scene with them, and they emerge as relatable and recognizable, with a natural four-way chemistry.

The main emotional thread is the turtles’ increasing sense of isolation from the world above, and the possibility that Krang’s technology might make them human. The conflicting emotions threaten to tear the team apart, and it’s up to Leonardo to keep them all together.

A lot of Appelbaum and Nemec’s asides are genuinely funny — even Megan Fox seems to be having fun with some of the dialogue — and the whole thing comes in at a punchy 112 minutes. Despite Bay’s heavy hand, there are scenes where Out of the Shadows succeeds in being exactly what a film like this should be: joyous.