The 2012 Teenage Mutant Ninja Turtles series, made by Nickelodeon, was an absolute gem throughout its 5-season run. The creators got to wrap up their major story arcs, like taking down the Shredder and his goons, despite Nickelodeon not giving them the amount of seasons originally promised to them. That being said, there was at least one plot thread left open. That particular plot thread is about a character named Timothy.

Timothy was a teenager who idolized the Teenage Mutant Ninja Turtles so much that he dressed up as them to fight crime (poorly) under the alias of “The Pulverizer.” Donatello felt bad for Timothy when the other Turtles didn’t want him to tag along on missions for his own safety. He vouched for him and took him under his wing. Unfortunately, things went wrong and Timothy became mutated. He didn’t become a cool superpowered animal like the Turtles or Leatherhead or any of the other slew of iconic heroes and villains, though. Instead, he transformed into a pile of organs covered in caustic sludge. He became a barely sentient monster known as Mutagen Man.

In order to keep the newly-mutated Timothy safe and others safe from him, Donatello froze him. He kept him frozen in a large canister with the intent of creating a retro-mutagen that would put him back to normal. He made a promise to the frozen Timothy that he will one day fix him. That day never came.

There are multiple times throughout the remainder of the series in which Mutagen Man is seen frozen in his canister in the background of Donnie’s lab. It serves as a painful reminder of one of the most tragic stories in the show and how it has yet to be resolved.

To make matters worse, the later seasons have Donatello actually get around to creating a retro-mutagen that can turn mutants back into humans. The Turtles even successfully use it on characters like April’s father and Baxter Stockman. Even if the Turtles are put in situations in which they must use whatever retro-mutagen they currently have in order to save someone or stop a villain immediately, it’s still proven that it’s possible. However, the retro-mutagen is never used on Timothy.

The poor kid is seemingly stuck being frozen forever. Donatello was wracked with guilt when things first went wrong. He even blamed himself for putting Timothy in danger. Then, over the course of the rest of the show, just apparently forgot about him even though he sees him every time he’s in his lab.

It’s quite odd for what is otherwise a fantastically well-written TV series to have such a devastating conflict left unresolved. This is one open plot thread that has been eating at fans since the series ended in 2017.

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