Teenage Mutant Ninja Turtles: Mutant Mayhem

Techno Cosmic Research Institute (TCRI) executive Cynthia Utrom sends a squad to hunt down rogue scientist Baxter Stockman, who has created a mutagenic ooze with which he intends to form his own mutant animal family, starting with a housefly. Baxter is interrupted by Cynthia's strike force and killed in the resulting explosion, while the mutagen falls into the sewers of New York City. The mutagen turns four turtle brothers-Leonardo, Raphael, Donatello and Michelangelo-and a rat named Splinter into humanoid mutants, whereupon Splinter adopts the turtles. Splinter distrusts humanity-particularly after one encounter where he and the turtles were chased away-and trains his sons in the art of ninjutsu, instructing them to only leave their sewer home to steal supplies. Over the years, the Turtles long to live with and like humans their age, much to Splinter's dismay.

Fifteen years later, the Turtles defeat a gang of criminals to recover a stolen moped belonging to a teenager named April O'Neil, revealing themselves and their origins. April, an aspiring journalist, has been investigating a series of robberies of TCRI technology by a criminal known as "Superfly". The Turtles plan to stop Superfly and, through April's reporting, win public acceptance as heroes. They intercept a piece of stolen technology and meet Superfly under the Brooklyn Bridge, discovering that he is not only a mutant himself, but leader of a mutant gang. Ecstatic to meet fellow mutants, the Turtles bond with Superfly and the others and he reveals their creation at the hands of Stockman, explaining that they evaded TCRI and are living on an abandoned ship in Staten Island. He then reveals that he plans to use the stolen technology to mutate every animal on Earth and create a world where mutants have dominance over humans.

The Turtles try to intervene, but the gang escapes with the equipment while a tracker TCRI installed on the equipment falls back with the Turtles, allowing them to be captured. At TCRI headquarters, Cynthia extracts the Turtles' mutagen, but April arrives with Splinter to rescue them. At the gang's hideout, Splinter and the Turtles convince them that their plan for domination will make them no better than the worst of humanity, and together they turn on Superfly, destroying his machine. However, the ooze falls into the water, combining marine wildlife with Superfly, who then transforms into a gigantic whale-like kaiju after grabbing animals from a nearby zoo. He attacks the city and the Turtles and other mutants attempt to stop him but are assumed by the public to be fellow monsters.

Leonardo finds his voice as a leader while April overcomes her anxiety and commandeers a news broadcast to explain the mutants' good intentions and the citizens of New York come to their aid. With the help of the citizens and other mutants, the Turtles drop a canister of TCRI retro-mutagen into Superfly's blowhole, turning him back into a collection of normal animals. Reconciling with Splinter, the Turtles, April, and the mutants are celebrated by the city. The Turtles enroll at April's high school, where they are embraced as heroes.

While the Turtles and April enjoy themselves at prom, they are under surveillance from Cynthia (holding the now unmutated Superfly captive), who plans to recapture the Turtles by enlisting the aid of the mysterious Shredder.

Following the release of Teenage Mutant Ninja Turtles (2014) and its sequel, Out of the Shadows (2016), Brian Robbins felt that the Teenage Mutant Ninja Turtles film series was in dire need of a reboot. He sought advice from longtime Turtles toy manufacturer Playmates Toys, who told him that the reboot should be an animated film. In 2018, Robbins discussed with newly appointed executive vice president of Nickelodeon Animation Studio, Ramsay Naito, who to bring onto the project. Seth Rogen was decided upon, and Jeff Rowe joined the project soon after. In June 2020, Deadline Hollywood reported that Nickelodeon Animation was developing a CG-animated Turtles film for Paramount Pictures. Rowe was hired to direct, from a screenplay by Brendan O'Brien. Rogen, Evan Goldberg, and James Weaver produced through their production company, Point Grey Pictures, which is credited alongside Nickelodeon Movies. Naito and Josh Fagen oversaw production for Nickelodeon and Point Grey, respectively.

In an August 2020 interview with Collider, Rogen said that the film would heavily lean into the teenage element of Turtles. He stated,

As a lifelong fan of Ninja Turtles, weirdly the 'Teenage' part of Teenage Mutant Ninja Turtles was always the part that stuck out to me the most. And as someone who loves teenage movies, and who's made a lot of teenage movies, and who literally got their start in their entire profession by writing a teenage movie, the idea of kind of honing in on that element was really exciting to us. I mean, not disregarding the rest, but really using that as kind of a jumping-off point for the film.

In June 2021, Rogen revealed a teaser image through his Twitter page, which contained school notes written by Leonardo, the film's original release date, and other details. By October 2021, the film was under the working title Teenage Mutant Ninja Turtles: The Next Chapter. Production designer, Yashar Kassai, elaborated on the project, "You anchor yourself enough in the familiar elements of it so that it is easily recognizable, but then you either add to or enhance some of the existing charm of the franchise." The title Teenage Mutant Ninja Turtles: Mutant Mayhem had been finalized by August 2022. Kyler Spears joined the film as co-director, signing on because he had worked with Rowe on his prior film, The Mitchells vs. the Machines (2021). J.J. Villard was commissioned to design the film's logo. Overall, the budget was $70 million at minimum.

Teenage Mutant Ninja Turtles: Mutant Mayhem received positive reviews from critics. The film's performances, screenplay, and stylized animation were widely praised, and several critics considered it the best Turtles film.

On the review aggregator website Rotten Tomatoes, 95% of 251 critics' reviews are positive, with an average rating of 7.6/10. The website's consensus reads: "With its unique visual style and a story that captures the essence of the franchise's appeal, Teenage Mutant Ninja Turtles: Mutant Mayhem is an animated treat for the whole family." Metacritic, which uses a weighted average, assigned the film a score of 74 out of 100, based on 47 critics, indicating "generally favorable" reviews. Audiences surveyed by CinemaScore gave the film an average grade of "A" on an A+ to F scale, while those polled at PostTrak gave it an 88% overall positive score, with 70% saying they would definitely recommend the film.

Lauding the film, Justin Chang of the Los Angeles Times called it "an unexpectedly delightful challenge to the critic's reflexive antifranchise mentality". Tom Jorgensen of IGN who gave the film an 8 out of 10 rating, spoke positively of it, though criticized the plot for being predictable. He wrote that the film "oozes confidence, energy, and heart" and represents "a new high for the Turtles on the big screen". Charlotte O'Sullivan of the Evening Standard, who awarded the feature 4 out of 5 stars, praised the portrayal of April O'Neil as well as Edeberi's performance of the character. She said that the film was "peppy, anarchic, doesn't talk down to teens, looks scrumdiddlyumptious, boasts an impeccably laconic soundtrack and gives us April O'Neil as we've never seen her before". Empire's John Nugent summarized in his 4 out 5 star rating review: "Inventively animated, giddily funny, and a surprisingly authentic take on the outsider experience: it is virtually impossible not to be charmed by these reptilian bros".

/Film's Rafael Motomayor gave the film a 9 out of 10 rating, saying that it "is not only a great introduction to the iconic franchise, but a fantastic film in its own right, and one of the best-looking movies of the year". Liz Miller of Consequence, who gave the film an A grade, commended the use of licensed tracks, writing that the montage set to Blackstreet's "No Diggity" "might be one of the most beautifully animated sequences of the year so far". Deadline Hollywood's Pete Hammond applauded the screenplay, humor, and performances of Abbey, Brown, Cantu, and Noon. He concluded, "Rogen has made his mark on a franchise that still finds new ways to smartly entertain amid all that mayhem".

In July 2023, a month before the film's release, it was announced that a sequel had been greenlit. It will feature the Shredder as the main antagonist who was teased at the end of Mutant Mayhem. Rowe is set to return as director alongside co-directors Spears and Kassai. Point Grey is set to co-produce again with Rogen, Goldberg, Weaver, Josh Fagen, and Ramsay McBean as producers. The film was originally set to release in theaters on October 9, 2026, but it was later pushed back to September 17, 2027, before being moved up to August 13, 2027. In December 2025, Rogen and Point Grey Pictures were in discussions with Paramount Skydance to produce a third film in the series.