Casey Jones (Teenage Mutant Ninja Turtles)

In the original Mirage series, Casey first appeared in the Raphael one-shot, by Kevin Eastman and Peter Laird. Casey was introduced as a violent, hot-tempered vigilante whose anger concerned even Raphael. The turtle stopped Casey from killing some muggers, causing an initial conflict between the two. This clash was quickly resolved, and Casey and Raphael became fast friends. Later, Casey came to the turtles' aid when they are attacked by the Shredder in April O'Neil's home. The vigilante even took the turtles to his grandmother's old farmhouse in Northampton, cementing his place with the group.[2]

In the Mirage series, Casey is extremely violent, even more so than Raphael, but he mellows throughout the course of the series. In Shades of Gray, Casey accidentally kills a teenager who tried to mug him. The incident sent him into a drunken spiral, damaging his relationship with April O'Neil.[3] His initial homicidal tendencies are especially present in his first appearance, although he never actually murders anyone in that instance.[4]

During the three-part episode City at War, Casey leaves the farmhouse and begins to drive to Los Angeles, planning to find April, but instead meets a pregnant woman named Gabrielle with whom he falls in love and marries. Gabrielle dies during childbirth and Casey is left to take care of her daughter, whom he names Shadow. After spreading Gabrielle's ashes, Casey returns to New York with Shadow to stay with his mother. In a chance encounter, Casey is reunited with April when she comes to buy the apartment building owned by Casey's mother. During this meeting it is revealed that Casey's real name is Arnold but prefers to use his middle name only.

Casey repairs his relationship with April and they begin dating. By volume four, he and April are married, raising Shadow as their daughter and trying to have a child of their own. April eventually leaves Casey and Shadow when April learns that she is a living drawing that was brought to life by a magic crystal. As April comes to terms with herself in Alaska, Casey takes to the nightclubs to drown his sorrows. He meets up with the Foot Clan leader Karai at one of these clubs and, after a few drinks, awakens at Karai's retreat with no memory of the night before, although Karai knows something of what had happened. This plotline was left unresolved as the fourth volume came to an abrupt end.

Although mentioned, Casey Jones never appears in the Archie Comics Teenage Mutant Ninja Turtles Adventures.

The fourth issue of the Dreamwave Productions series (based on the 2003 animated series) focused entirely on Casey Jones. When Casey was a little kid, he was worried that his dad should give into the Purple Dragons and their protection racket, lest something bad happen. Mr. Jones becomes violent and tells Casey that he is playing on his team and that a Jones never gives in (nearly punching Casey in a violent rage). Mr. Jones hears something and figures it is the Purple Dragons breaking into his store. Casey watches as his father's store burns to the ground. The Purple Dragon leader, Hun, then smacks Casey aside with the encouragement that his father pay up. Casey breaks a bottle and stabs Hun in the leg with it. Furious, Hun has his thugs beat Casey to a pulp. Before being thrown out of the hospital because he lacked insurance, Casey is diagnosed with brain damage from the beating. Shortly after that, Mr. Jones goes searching for Hun to get revenge and vanishes. Casey's mom then goes searching for her husband and vanishes, too. Casey drifts off into a delusional state, reassuring himself that his father and mother are still alive, just waiting for Casey to clean the streets of all the Purple Dragons before they can return.

In the TMNT series released by IDW Publishing, Casey is a young college scholarship holder. Upon his mother's death by cancer, his father, formerly Hun of the Purple Dragons, became an alcoholic thug who would vent his daily frustration on his son. On one such occasion, Casey was saved from another violent beating by Raphael, who had at that time lived a solitary life as a street vagrant following his mutation (unaware that he had a family searching for him), and the two quickly became fast friends and fellow vigilantes until Raphael was reunited with his family, at which point Casey was introduced to and befriended the other three turtles as well. He later meets April when she becomes his tutor, and introduces her to the turtles. After an especially violent beating by his father, Casey comes to live with the turtles, while his father returns to the Purple Dragons.

In the 1987 animated series, Casey Jones is a crazed vigilante with a "Dirty Harry" like persona, who goes after all sorts of criminals, from robbers to litterers. He never takes off his mask on screen, even when once going undercover in a business suit.

Appearing in only five episodes of the series, this version of Casey does not play a role as central as his comic book counterpart: He does not have a friendship with Raphael, nor a relationship with April – he does not even encounter her until season 5's Leonardo Cuts Loose, though later they do team up in episodes Night of the Rogues and Cyber-Turtles. Casey was voiced by Pat Fraley. In the Japanese version, he was voiced by Issei Futamata and Akio Ōtsuka (NHK-BS2 Version).

In the 2003 animated series, Jones has a much more important role. He speaks in a Brooklyn accent, voiced by Marc Thompson in English and Tokuyoshi Kawashima in Japanese. This incarnation's personality is on par with Raphael's. Raphael first meets Casey while the vigilante tries to stop a mugging by the Purple Dragons. Seeing a lot of himself in Casey, Raphael tries to reason with him and prevent him from letting his anger get the best of him (Raphael himself had just almost severely injured Michelangelo and was overwhelmed by guilt). Though initially uninterested in what he has to say, Casey eventually bonds with Raphael after he loses to Raph in a bike race and begins listening to his lessons. Casey, Raphael, and the other turtles proceed to team up and defeat a gang of Purple Dragons. From this point on, Casey becomes a valuable ally of the Turtles, and has a closer friendship with Raphael than in any other incarnation.

Casey's backstory is fleshed out over the course of the series. When he was a child, his father's shop was burned down by Hun and the Purple Dragons for being denied protection money.[5] Despite being threatened not to, his father (Arnold Casey Jones Sr.) later went to the police over it. It is implied that he was killed for doing so.[6] This gave Casey his hatred for crime and an essential lifelong vendetta against the Purple Dragons. This backstory was later expanded upon in the Dreamwave comics and adopted into the Mirage series.

It is revealed in episode "The Lesson" that he and the Turtles had met when they were kids, although neither the Turtles nor Casey are aware of the truth. During a trip to the surface, the young Turtles witness bullies picking on young "Arnie". Disguising themselves as a human child, they attempt to teach him self-defense. However, their unique perspectives and attitudes resulted in more trouble than help. In the end, however, young Casey angrily jumps to the defense of a friend against the bullies, proclaiming they were no match for "Arnold Casey Jones!" In a bit of foreshadowing, he uses a bully's hockey stick against them.

His main catchphrase is the battle cry "Goongala!". It is also revealed in "The Lesson" that this came from a young Casey being unable to pronounce "gorogoro-sama", a battle cry literally meaning "Mr. Thunder", that young Michelangelo kept trying to teach him. "Goongala" was the best he could come up with.

Despite his lack of intelligence and apparent incompetence, he was early on in the series referred to by Hun as "Our (the Purple Dragon's) greatest enemy", and a fighting tournament was held to see which Dragon would have the honor of killing him, indicating how serious a threat the criminal underworld views him as.

In the series, Casey has a good heart, but is easily enraged and occasionally bumbling. He loves motorcycles. In a symbolic way, he sees the Turtles as the little brothers he never had. As such, he often comes to their aid against the Shredder, the Foot Clan, or other enemies.

Early on, Casey meets April and there is an initial attraction. However, their conflicting personalities lead to frequent arguments at first. Over time, however, they start dating and a serious relationship develops. In the Back to the Sewers (seventh) season, Casey proposes marriage to her. In the finale "Wedding Bells and Bytes", they are married, with Raphael serving as the best man and Michelangelo as the maid of honor. Many recurring characters were in attendance and the ceremony performed by the Fugitoid. In the Fast Forward (sixth) season, the Turtles and Splinter are transported to 2105, where they meet April and Casey's great grandson, Cody Jones, the heir to O'Neil Tech, a company created by April, Casey and Donatello after the turtles return to their own time. One of Cody's inventions, the Turtle X armor, resembles Casey's hockey mask.

Casey Jones appeared for the first time in the second season of the 2012 animated series.[7] In the tie-in prequel comic on the official website, Raphael spots some graffiti on a sewer wall that says, "Jones is everywhere!", which also had his iconic hockey mask painted beside it. In a new trailer from IGN, it is shown that Casey thinks he is the "Last Hope" for New York City. He seems to know about mutants, which is seen when he rescues April from Mutagen Man and is shown to be able to defeat him on his own. An interview with show creator Ciro Nieli on IGN elaborates:

I asked about Casey Jones on the series, and Nieli replied, "Casey Jones will show up in the second season," noting he did not want to give too much away, but that, "We'll take our time introducing him." Casey will also be a high school student, but "Maybe a couple years older – he got held back."[8]

He is voiced by Josh Peck.[9] He is introduced in the episode "Mutagen Man Unleashed" as a hockey player who April tutors in school.

He later becomes a vigilante who hunts criminals, mutants and anything that he thinks threatens "his" city in season two's episode "The Good, The Bad and Casey Jones" and becomes an ally to the turtles, specifically Raphael who becomes his best friend. He also has rivalry with Donatello due to their mutual feelings for April. Casey also has a penchant for speaking in third-person and has a fear of rats, which includes Splinter to an extent.

As the series progresses, his rivalry with Donatello is lessened, and he becomes closer to the whole team in general. In season three's "Casey Jones VS. The Underworld" Casey decides to start hunting crime on his own and eventually meets his new own archenemy, Hun, the new leader of the Purple Dragons. He is defeated, at first, but later defeats Hun and prolongs Shredder's plans. He is later one of only six inhabitants of Earth-the others being April and the Turtles-to be rescued before the planet is consumed by an artificial black hole.

In the Season 4 finale, "Owari" Casey assists the Turtles in avenging the death of Splinter. When the Turtles gear up for a mission, Casey gets a new mask that bears a strong resemblance to his comic counterpart.

In the alternate future seen in Raphael: Mutant Apocalypse, Casey was one of the many humans that died as a result of a giant Mutagen bomb hitting the planet. Raphael kept his skull and helmet, which was attached to a bomb that he used to take down Maximus Kong's vehicle.

In the Monstrous Tales saga, Casey turns into a vampire, along with April, Donatello and Raphael, until he returns to normal, due to Mikey defeating Dracula.

In the Crossover Tales saga, Casey assists the Turtles and their 1980s counterparts in stopping Krang and the 1980s counterpart of the Shredder. He and April enlists Karai and Shinigami to hunt down Bebop and Rocksteady in "The Foot Walks Again". Later, Casey teams up with the Turtles and the Mighty Mutanimals to put an end to Zeck and Steranko in "The Big Blowout".

Casey Jones as depicted in Rise of the Teenage Mutant Ninja Turtles: The Movie.

In Rise of the Teenage Mutant Ninja Turtles, the series introduced a female incarnation of the character named Cassandra Jones, voiced by Zelda Williams. Before her identity was revealed, she was originally known as The Foot Recruit of the Foot Clan who debuted in "Hot Soup: The Game."

By the four part episode "Finale," Shredder regained his power of speech and made the Foot Recruit his new general after the Foot Lieutenant and the Foot Brute were trapped upon the collapse of Baron Draxum's laboratory. When at the Crying Titan, Shredder had the Foot Recruit prepare the ritual where it combined with the Empyrean within the Crying Titan which would enable him to drain Splinter's essence. During the Turtles and April's fight with Shredder, Cassandra defected to their side and helped them, Baron Draxum, and the spirits of the Hamato Clan's ancestors defeat the Shredder while returning Oroku Saki's spirit to them.

A second, more traditional version of Casey appears in Rise of the Teenage Mutant Ninja Turtles: The Movie, voiced by Haley Joel Osment. This Casey hails from the year 2044, and travels back in time to warn the Turtles of an impending alien invasion by the Krang, helping them defeat the aliens after the invasion begins.[10] After the Krang's defeat, it is revealed that Cassandra was also fighting the invaders on her own, and Casey reveals that he is her son.