Teenage Mutant Ninja Turtles fans are expressing both shock and sadness at Casey Jones' exclusion from the upcoming TMNT animated film Mutant Mayhem.

Fans were initially worried that the beloved hockey mask-wearing vigilante might not be in the film when the voice cast for Teenage Mutant Ninja Turtles: Mutant Mayhem was announced during the 2023 Nickelodeon Kids' Choice Awards. While fans learned who would be voicing the titular turtles -- as well as TMNT mainstays April O'Neil, Splinter and Bebop and Rocksteady -- Casey Jones' name was absent leading many to wonder if the character would not be included in Mutant Mayhem. The first trailer for the film has only heightened those concerns, with the character nowhere to be found in the two-minute teaser. At this time, no one involved with the production of Mutant Mayhem has outright confirmed or denied if Casey Jones will be in the film.

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Although Casey Jones may be absent from the turtles' big screen return, several other fan-favorite characters from the Teenage Mutant Ninja Turtles franchise have been confirmed to appear in the upcoming film. These include Hannibal Buress as Genghis Frog, Rose Byrne as Leatherhead, Ice Cube as Superfly, Natasia Demetriou as Wingnut, Post Malone as Ray Fillet, Maya Rudolph as Cynthia Utrom and Paul Rudd as Mondo Gecko. It is currently unknown how these characters will factor into the film's narrative, which will focus on the Turtles looking for acceptance.

Heroes in a Half Shell

"In Teenage Mutant Ninja Turtles: Mutant Mayhem, after years of being sheltered from the human world, the Turtle brothers set out to win the hearts of New Yorkers and be accepted as normal teenagers through their heroic acts," reads the film's brief synopsis. "Their new friend April O'Neil helps them take on a mysterious crime syndicate, but they soon get in over their heads when an army of mutants is unleashed upon them."

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TMNT Heads Back to the Big Screen

Mutant Mayhem will be the seventh theatrical Teenage Mutant Ninja Turtles film, as well as the first theatrical animated film starring Leonardo, Michelangelo, Donatello and Raphael since 2007's TMNT. The upcoming film will also be the first theatrically released TMNT movie since the 2016 live-action/CGI film Teenage Mutant Ninja Turtles: Out of the Shadows. Jeff Rowe, best known for co-directing The Mitchells vs. the Machines, is directing Mutant Mayhem from a screenplay by Brendan O'Brien. Seth Rogen will produce alongside Evan Goldberg and James Weaver through their company Point Grey Pictures.

Micah Abbey, Shamon Brown Jr., Nicolas Canto and Brady Noon will voice the titular pizza-loving turtles Donatello, Michelangelo, Leonardo and Raphael, respectively, with Ayo Edebiri as April O'Neil. the rest of the voice cast includes Giancarlo Esposito as Baxter Stockman, Jackie Chan as Splinter, John Cena as Rocksteady and Rogen as Bebop.

Teenage Mutant Ninja Turtles: Mutant Mayhem opens in theaters on Aug. 4.

Source: Twitter