The Joker is a homicidal maniac and the archenemy of Batman. Though his precise origin is unknown even to him, it is known to have been forced to swim through a vat of chemicals which turned his skin white, his hair green, and left his face permanently locked in a double Glasgow Grin.
Due to his nature, the Joker suggested many possible origins for how he came to be. Even before becoming the Joker, his DNA was not available on any records. One of his favorites was that he lived with his murderous Aunt Eunice. An abusive guardian, she washed his skin with bleach, resulting in irreparable brain damage as well as the drainage of all pigmentation from his skin.
The Joker began as “Red Hood One,” the leader of the Red Hood Gang, comprised of blackmailed individuals from the middle and upper classes of Gotham that the Red Hood kept under his sway. With the ideology of pointless violence, the gang dared the authorities to try and catch them all. He first faced off against Bruce Wayne when the returned billionaire turned vigilante rescued some hostages from the madman.
Hijacking and robbing Oswald Cobblepot’s personal blimp, Red Hood One got his hands on some stolen WayneTech weapons that, when rewired, could cause some real damage.
Having been tipped off by Edward Nygma, the Red Hood sent his gang to kill Bruce Wayne, catching the billionaire in an explosion in his brownstone. Taunting Wayne as he lay dying, Red Hood One added insult to injury by shooting two bullets through a portrait of Wayne’s deceased parents before leaving the future vigilante to his injuries.
As the tales of the urban legend known as the Batman rose in the wake of Wayne’s attempted assassination, the ranks of the Red Hood Gang began to slowly dwindle bit by bit, each member caught one by one. Having discovered Red Hood One’s plan, Wayne, having recovered from their last encountered, blew the gang’s cover at Ace Chemical Plant where the criminals were planning to steal flesh-eating chemicals. Realizing the jig was up, the Red Hood Gang led an assault there against the Batman and the GCPD.
Though Red Hood One attempted to escape in a helicopter, Batman fired his grappling line around his enemy’s ankle, yanking him from the aircraft, and sending them both plummeting through the weakened roof of the chemical plant. Almost falling into a vat of chemicals, Red Hood One was caught by Batman, who attempted to save the criminal’s life. Claiming this moment to only be the beginning, the gang leader broke free of his savior’s grasp and plummeted into the chemicals below. The man who was Red Hood One, though, despite Batman’s prediction that the chemicals were enough to kill him, would only mutate from his exposure in the vat both mentally and physically into the criminal that would later reappear as The Joker.
When Red Hood One first resurfaced as the Joker, his first attempted crime was trying to poison the Gotham Reservoir, an act that Batman successfully stopped. In and out of Arkham Asylum constantly, Joker began to gain a reputation as a notorious criminal. In one of his stays at the asylum, the madman actually managed to seduce his psychiatrist into letting him escape and join him as his criminal accomplice Harley Quinn.
One of Joker’s early plans drew the attention of the Gotham Gazette and, in particular, one of their journalists Tommy Blackcrow. Trying to investigate the clown that he clearly underestimated, Blackcrow was captured by Joker and, still undaunted, proceeded to tell the madman that he’s probably the way he is because he doesn’t have any friends, a comment that Blackcrow later regretted when Joker took it upon himself to make the journalist his best friend.
As years passed, Joker’s crimes became more violent, such as torturing and paralyzed Barbra Gordon and even killing the second Robin (Jason Todd). Again and again, Batman defeated Joker and sent him to Arkham, but his crimes had now hit much closer to home.
The Joker was a straightforward homicidal maniac killing more than 3 dozen people in his first run in the Batman series. In his first appearance, he left his victims with smiles on their faces after their deaths, something that has become a trademark for the character throughout his many years in publication. In his first appearance, the Joker challenged both the police department as well as Batman when he threatened to kill three people.
The Joker trapped Robin, Dick Grayson, and was prepared to kill him until the Batman showed up and stopped him. This story would be retold in 2005’s Batman: The Man Who Laughs.
In “The Joker Walks His Last Mile” Joker is sentenced to the electric chair. He escaped by faking his own death and when captured later on he could not be electrocuted due to the Double Jeopardy law. The Joker pretended to be a good citizen but soon fell into his old habits.
In his last appearance in Earth-Two Continuity, Bruce Wayne was revealed to be The Batman, and recently died. The Joker refused to believe this and began to destroy Gotham City hoping that Batman simply retired. Dick Grayson impersonated the Batman long enough for Joker to be taken into custody.