Teenage Mutant Ninja Turtles: Mutant Mayhem

In June 2020, Deadline Hollywood reported that Nickelodeon Animation Studio was developing a computer-animated Teenage Mutant Ninja Turtles film for Paramount Pictures. The film marks Nickelodeon Animation's first CG-animated theatrical production. Jeff Rowe was hired to direct the film, with Brendan O'Brien writing the screenplay. Seth Rogen, Evan Goldberg, and James Weaver produced the film through their company, Point Grey Pictures, who previously worked with O'Brien on Neighbors (2014) and its sequel, Neighbors 2: Sorority Rising (2016). Brian Robbins, the president of Nickelodeon, said that "adding Seth, Evan, and James' genius to the humor and action that's already an integral part of TMNT is going to make this a next-level reinvention of the property."[3]

In an interview with Collider in August of that year, Rogen said that the film would put a heavy focus on the teenage element of Teenage Mutant Ninja 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."[4]

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.[5] Later in October of that year, the film was under the working title Teenage Mutant Ninja Turtles: The Next Chapter. In an interview with Variety, the film's production designer, Yashar Kassai, elaborated on the project by saying, "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."[6]

In August 2022, along with its logo, the film's official title was revealed as Teenage Mutant Ninja Turtles: Mutant Mayhem.[7] The logo was designed by J.J. Villard of King Star King, who made several concepts and let the film crew pick their favorite.[8]

On March 4, 2023, during the Kids' Choice Awards, Rogen revealed that actors Nicolas Cantu, Shamon Brown Jr., Micah Abbey, and Brady Noon (all of whom were in attendance) had been cast in the voice roles of the Turtles: Leonardo, Michelangelo, Donatello, and Raphael, respectively.[2][9] This marked the first time teenagers had been cast in the roles.[10] Other casting revealed in the ceremony included Jackie Chan as Splinter, Ayo Edebiri as April O'Neil, Rogen as Bebop, John Cena as Rocksteady, Hannibal Buress as Genghis Frog, Rose Byrne as Leatherhead, Natasia Demetriou as Wingnut, Paul Rudd as Mondo Gecko, Post Malone as Ray Fillet, Giancarlo Esposito as Baxter Stockman, and Ice Cube and Maya Rudolph as the original characters, Superfly and Cynthia Utrom, respectively.[11] Cena previously voiced the villain Baron Draxum in the first season of the animated series Rise of the Teenage Mutant Ninja Turtles (2018–20).[12]

As opposed to having each actor record their voice roles independently from the other cast members, as is the custom for animation, it was opted to have multiple actors record simultaneously in the same room. A single recording session could include up to seven actors.[13] This allowed for performances with a lot of improvisation and was partly influenced by Rogen's experience on The Lion King (2019).[14] Rogen commented, "We always recorded in big groups of people so we could improvise in big groups and kind of talk over each other and really try to give the scenes [spontaneity]." He praised Cantu, Brown, Abbey, and Noon in particular and said that they tried to "capture the way they actually interacted with each other." He recalled:

I remember we did one recording session with them and they would all hang out together in the kitchen of the recording studio, and they would all just talk over each other and make fun of each other; screaming at each other. And I remember being like, ‘Oh, this is what we have to capture’. Like, this is the energy of the movie. That's when we started recording them all simultaneously. And we would tell them to essentially improvise all of their lines, and we would guide them and pitch them stuff.[13]

In August 2022, it was announced that the film would be animated by Mikros Animation, in Montreal and Paris, alongside Cinesite's Vancouver facilities.[15][16] Andrea Miloro, the president of Mikros Animation, said that for over two years, their two global teams had created "cinematic and several unique animation styles" for the film and called it the first of its kind for the studio.[17]

Rowe was inspired by sketches he made in school notebooks as a teenager and wanted the film's animation to reflect a similar feeling.[18][19]

In February 2023, Rogen said that Rowe compared the film's soundtrack to that of the 1999 video game Tony Hawk's Pro Skater and revealed that it will incorporate songs from the title. He described it as a "random assortment of music" that fits together well and shares the "same energy and spirit."[20]