Warning: This post contains spoilers for Teenage Mutant Ninja Turtles: Mutant Mayhem

Teenage Mutant Ninja Turtles: Mutant Mayhem included plenty of familiar faces from TMNT history, but Casey Jones was not one of them. The latest animated TMNT adventure — the seventh theatrical film in the franchise — pits the titular characters against the villain Superfly as he works to execute his nefarious plans. The animated feature is full of colorful characters, each with their own arcs and personal journeys. And despite featuring April O’Neil, who is voiced by The Bear’s Ayo Edebiri, Casey Jones is surprisingly missing in action.

Arnold Bernid “Casey” Jones was first introduced in the 1985 comic Raphael: Teenage Mutant Ninja Turtle and has since become a notable ally to the Teenage Mutant Ninja Turtles. Casey is often portrayed as a vigilante in his own right, sporting a hockey mask and weapons including a hockey stick and bat, among others. Casey has typically appeared alongside April, his romantic partner, across various TMNT media, including the live-action films. For Teenage Mutant Ninja Turtles: Mutant Mayhem, however, Casey was left out of the story completely. He’s not mentioned once, but there’s a reason why he isn’t in the animated feature despite being a prominent figure in TMNT history.

Casey Jones Didn't Fit With TMNT Mutant Mayhem's Story

Considering the plot of Mutant Mayhem, Casey Jones simply didn’t fit into the overall story, which was primarily focused on the Teenage Mutant Ninja Turtles coming of age. With the core of the story being about the mutants and acceptance, it makes sense that Casey wouldn’t figure into the story as authentically as April, who has the friendship and journalism angle. What’s more, April’s story complemented the TMNT’s own, with both her and the mutant foursome learning that being liked by others shouldn’t be the driving force behind their actions. Casey being a vigilante wouldn’t have meshed well with the film’s premise, either.

Mutants who needed to achieve vigilante status before a human could so that people would see they weren’t trying to harm anyone, but save them. While Casey has mellowed out as a character over time, he has a tendency towards violence that wouldn’t have served the Teenage Mutant Ninja Turtles well. And since the Turtles and April are still teenagers, it’s possible Casey hasn’t yet met April at all yet, especially considering that she didn’t really have any friends and was mocked for vomiting on-air. In Mutant Mayhem, the Turtles are still building their reputation and allies, so it makes sense Casey was left out of the equation.

TMNT Mutant Mayhem 2 Can Better Introduce Casey Jones

With a Teenage Mutant Ninja Turtles: Mutant Mayhem sequel on the way, Casey Jones is better off being introduced in a story involving Shredder, who arrived in the film’s mid-credits scene. Now that the main characters have been introduced, there’s room to bring on new characters, which is where Casey Jones comes in. Casey could be introduced as a new student at April’s high school in the sequel, and his connection to her might be a way into the world of the Teenage Mutant Ninja Turtles. It’s possible Casey Jones, who’s got plenty of great combat skills, will help the foursome defeat Shredder and whatever else TCRI has in store.