This Friday, "Teenage Mutant Ninja Turtles: Out of the Shadows" -- the sequel to 2014's "Teenage Mutant Ninja Turtles" -- swings into theaters, and reviews for the film have started rolling in. Despite a 31% on reviews-conglomerate RottenTomatoes, critics largely agree that fans will love this enjoyable, if not groundbreaking film.

Chicago Sun-Times' Bill Zwecker gave the film 2.5 stars, saying, "Despite its flaws, 'Teenage Mutant Ninja Turtles: Out of the Shadows' should provide a bit more than 100 minutes of fun and frothy entertainment for the fans of those pizza-loving terrapins."

"There is no doubt that 'Teenage Mutant Ninja Turtles: Out of the Shadows' is head-and-shell better than its predecessor. It is, in fact, superior in nearly every way. It is a 'Turtles' film for 'Turtles' fans," agrees IGN's John Lasser. "As such, it may leave some out in the cold, but it points the franchise in the right direction and makes future films something to look forward to as opposed to something to dread."

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"I cannot think of a time when a franchise starter as terrible as 'Teenage Mutant Ninja Turtles' produced a sequel as good as 'Teenage Mutant Ninja Turtles: Out of the Shadows,'" wrote Forbes' Scott Mendelson. "But the second time is truly the charm, as director David Green's lively, colorful, and enjoyable sequel is everything the first film should have been. The film is truly turtle-focused, with a story that offers understandable conflict and entertaining interactions for our heroes in a half-shell. Kids will love it, and adult fans of the property will get the 'TMNT' movie they always wanted. Look, this isn't 'The Dark Knight,' but it's easily (by default?) the second best 'Teenage Mutant Ninja Turtles' movie ever made... The first film was a cowabummer. This second time out is such an 180-degree turnaround, the likes of which I don't think I've ever seen for a franchise like this, that it gives me renewed hope for 'Justice League.'"

Nerdist's Luke Y. Thompson gave the film 4.5 stars, saying, "It's quickly apparent, unlike last time, that you are watching a movie made by and for fans. Sure, Stephen Amell's Casey Jones feels so childlike as to almost come off idiotic, and Megan Fox is no master thespian. Yet none of that matters -- the Turtles themselves (Noel Fisher, Alan Ritchson, Jeremy Howard and Pete Ploszek) are great, and the action sequences are both funny and exciting, particularly an extended skydive-turned-river-chase through Brazil."

"The movie suffers from being the same shape as so many modern blockbusters, and the plot in the second half of the film is basically another riff on the 'reach the glowing doodad on a roof to prevent the end of the world' structure," HitFix's Drew McWeeny explained. "But the focus on the Turtles and the film's overall amiable sense of goofball humor carries the day, and my kids, fans of both the old cartoon and the latest series, were delighted by things like the giant garbage truck Donatello invents and the way Krang appears as a weird brain-looking alien sticking out of a robot's stomach. They found the entire thing accurate to what they love about the property, and watching them watch the film was as much fun for me as the movie itself.... Will this win over people who find the whole thing ridiculous? Nope. This is a film for fans of the 'Teenage Mutant Ninja Turtles,' and it feels like an affectionate, energetic effort, clearly coming from a place of real appreciation for why these characters have endured."

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However, not every critic was willing to overlook the film's flaws in the name of nostalgia and fun. According to Empire's Emma Thrower, "The slick first third may seem like a different franchise to the turtles' 2014 outing, but 'Out Of The Shadows' soon unravels as the Retro-Mutagen cements its status as yet another uninspired MacGuffin in yet another bland final act containing yet more people looking up at the sky. Krang is gleefully grim ("it's like a chewed up piece of gum with a face!"), but, considering he and his exosuit barely feature, doesn't deserve the final boss level-esque climax he is awarded."

The Guardian's Mike McCahill gave the film 1 star, writing, "'Out of the Shadows' is assembled with consummate slickness, nominal director Dave Green -- following up 2014's semi-heartfelt 'Earth to Echo' -- approving many of the right effects shots. Yet only Bay could conceive of blowing this much time and cash on identifying the exact spot at which zesty, subversive trash (as the Turtles might once have been) sours into ugly, empty junk, assembled solely to school our young in brute market forces and indiscriminate consumption. Our former heroes in a halfshell have become hulking, cold-bloodied bullies, demanding our pocket money and offering nothing in return -- save a joyless, two-hour noogie such as this."

CBR's own Kristy Puchko also weighed in on the film, writing, "Michael Bay's production company has radically course corrected with the aptly titled, 'Teenage Mutant Ninja Turtles: Out of the Shadows,' which not only puts the brawny brothers at the center of the story where they belong, but also folds in a cavalcade of other fan favorites, like Casey Jones, Kraang, Bebop and Rocksteady. Undeniably better than its predecessor, this spirited sequel offers more laughs, more fun and more turtles, but some of the same old disappointments."

"Teenage Mutant Ninja Turtles: Out of the Shadows" opens Friday.