The Teenage Mutant Ninja Turtles are an incredible success story, born out of relative obscurity in 1984 and quickly skyrocketing to worldwide popularity. While the turtle protagonists inevitably undergo personality adjustments in various media, their first human compatriot, April O'Neil, goes from sidekick to standalone hero - and it's a significant journey.

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TMNT's April O'Neil Was Originally a Computer ProgrammerMirage Studios African American April O'Neil in front of the Teenage Mutant Ninja Turtles

In the black-and-white TMNT comics from Mirage Studios, the Turtles save April O'Neil from the Mousers, small robots created by Dr. Baxter Stockman and April herself. In this original iteration, April isn't a hard-nosed, intrepid TV journalist -- she starts out as a computer programming whiz. April is hired to help Dr. Stockman create the Mousers in order to eradicate New York's rat infestation, unwittingly providing the mad doctor with the tools to take over the city. Once she uncovers Stockman's nefarious plan, the doctor decides he has to get rid of her. The Turtles rescue April and take her back to their lair and the rest is, as they say, history.

Throughout the Mirage Studios comics, April sticks by the Turtles, befriends and nearly marries human teammate Casey Jones, nearly dies, takes on a vigilante identity and then discovers she's not really human -- she's a drawing. The "Kirby and The Warp Crystal" arc from the miniseries Donatello, introduces a crystal that can bring drawings to life. Later, the comics reveal that April's father, dreaming of the daughter he hoped to someday have, drew a picture of her with a pen that had the magic crystal attached to it. In this iteration of April, the character goes to some strange, dark places, and while she isn't a standalone hero, she is rarely seen as the sidekick she becomes in future adaptations.

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1980s' TMNT Cartoon Introduced April the News Reporter

Leonardo, Raphael, Michaelangelo and Donnatello posing for the 1987 TMNT Cartoon

The TMNT '80s cartoon series features a very different April O'Neil. Red-haired and perennially wearing a yellow jumpsuit, April is a reporter for Channel 6 News. Following a hot news tip, April is attacked. She heads to the sewers in her attempt to escape, and the Turtles come to her rescue.

April is initially wary, assuming the Turtles are behind a number of thefts she has been investigating. They team up to find the true culprits and continue to work together throughout the series. Unfortunately, she is somewhat one-dimensional in this iteration of the franchise's TV run. She acts more as the Turtles' connection to the outside world, rather than a member of the team itself, more often requiring rescue and aid than providing it.

The Archie Comics TMNT run started in 1988 as an extension and adaptation of the original TV series. April is once again in her yellow jumpsuit, but the continuity ends there. Not content to stick to her role as helpless sidekick, April begins training with Splinter and becomes a formidable fighter in her own right.

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The '90s TMNT Film Portrayed April As a Sidekick and Reporter

The Teenage Mutant Ninja Turtles peek out of the sewer in the 1990 live action film

April and the Turtles hit the big screen in 1990. While forgoing the yellow jumpsuit, live-action April O'Neil (played by Judith Hoag) does, at one point, sport a very yellow trench coat. In this first film adaptation, April is a supporting character at best.

In two other live-action films from the '90s, Paige Turco takes over the role, but the character doesn't deviate much from her initial introduction. In short, these film versions of April O'Neil reflect the early TV series renditions and position her solidly in the sidekick seat.

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21st Century April O'Neil Is Both Fighter and Scientist

Teenage April O'neil and the TMNT posing in the 2012 Animated Series

The 2003 Teenage Mutant Ninja Turtles animated TV series sees an April O'Neil akin to the Archie Comics iteration. While she is a scientist in this series, she is also a fighter thanks to some training from Splinter. In 2011, the IDW comics introduced April as a more pivotal character and her father is actually responsible for the compound that mutates Splinter and the Turtles in the first place.

In the 2012 animated series, April (a teenage girl) works hard to prove herself as a friend and compatriot to the Turtles, becoming a fighting force and full-fledged team member thanks to Splinter's training. Two years later, Megan Fox's take on April O'Neil is introduced in the feature film franchise reboot. Back to a being news reporter, this April O'Neil isn't anyone's sidekick. She's even given one of her own in Will Arnett's character, Vern Fenwick. In the 2018 Rise of the Teenage Mutant Ninja Turtles animated series, April is a streetwise teen. She has a much more aggressive personality and takes action considerably more than any of her other iterations.

All told, April O'Neil has changed a lot over the past 35-plus years. While she was an amazingly dynamic character in the first iteration of the franchise, she was still a supporting character. As the franchise has developed, she has come into her own. More recent iterations of the character portray her as younger and sharper, but the "real" April O'Neil is arguably found in a mash-up of the original version and the ongoing IDW run: Complex, damaged and strong, but not necessarily a fighter.