Two-Face

History
At 26, Dent is the youngest district attorney ever to serve Gotham City, and is nicknamed "Apollo" for his clean-cut image. He is elected about six months before Batman begins his war on crime.

Dent, Captain James Gordon, and Batman forge an alliance to rid Gotham of crime boss Sal Maroni, who is murdered by Carmine Falcone's son Alberto. Falcone hires the corrupt Assistant District Attorney Fields to disfigure Dent with sulfuric acid. Two-Face gets his trademark coin from his abusive father, who would employ the coin in a perverse nightly "game" that would always end with a beating. This would instill in Dent his lifelong struggle with free will and his eventual inability to make choices on his own, relying on the coin to make all of his decisions. Eventually, the scarred Dent takes his revenge on Fields and Carmine Falcone, leading to his incarceration in Arkham Asylum.

During a much later period, Two-Face is revealed to have murdered Jason Todd's father, who had been one of his henchmen.

Eventually, in Arkham, the doctors in the asylum attempt to wean him off the coin by replacing it with a die and eventually a tarot deck, giving him 78 options. The treatment fails due to Dent being unable to make decisions. Batman returns the coin, telling him to use it to decide whether to kill him. He tells Batman that the coin landed scar face down, and Batman leaves safely, but the next scene shows the scar face up, meaning that he inexplicably chose to let Batman live due to it being April Fools' Day.

After the Gotham earthquake, Two-Face carves out a portion of the ruined city for himself and takes up residence in Gotham City Hall, maintaining a sophisticated lifestyle. His empire is brought down by Bane (employed by Lex Luthor) who destroys Two-Face's gang during his destruction of the city's Hall of Records. Two-Face kidnaps Commissioner Gordon and puts him on trial for his activities after Gotham City was declared a No Man's Land, with Two-Face as both judge and prosecutor. Gordon plays upon Two-Face's split psyche to demand Harvey Dent as his defense attorney. Dent cross-examines Two-Face and wins an acquittal for Gordon, determining that Two-Face has effectively blackmailed Gordon by implying that he had committed murders to aid the Commissioner.

During all this, Two-Face meets detective Renee Montoya. Montoya reaches the Dent persona in Two-Face, and is kind to him. He falls in love with her, though the romance is one-sided. And eventually, in the Gotham Central series, he outs her as a lesbian and frames her for murder, hoping that if he takes everything from her, she will be left with no choice but to be with him. She is furious, and the two fight for control of his gun until Batman intervenes, putting Two-Face back in Arkham.

In the Two-Face: Crime and Punishment one-shot book, Two-Face leads a crusade against Gotham City, culminating in the capturing of his own father to humiliate and kill on live television for the years of abuse he suffered. This story reveals that, despite his apparent hatred for his father, Dent still supports him, paying for an expensive home rather than allowing him to live in a slum. At the end of the book, Harvey and Two-Face argue in thought, Two-Face calling Harvey "spineless." Dent proves Two-Face wrong, however, choosing to jump off a building and commit suicide just to put a stop to his alter ego's crime spree. Two-Face is surprised when the coin flip comes up scarred, but abides by the decision and jumps. Batman catches him, but the shock of the fall seems to (at least temporarily) destroy the Two-Face side of his psyche.

In Two-Face Strikes Twice, Two-Face is at odds with his ex-wife Gilda, as he believes their marriage failed because he was unable to give her children. She later marries Paul Janus, a reference to the Roman god of doors who had two faces, one facing forward, the other backward. Two-Face attempts to frame Janus as a criminal by kidnapping him and replacing him with a stand-in, whom Two-Face "disfigures" with makeup to make it look as if Janus has gone insane just as Two-Face had. Batman eventually catches Two-Face and puts him away, and Gilda and Janus reunite. Years later, Gilda gives birth to twins, prompting Two-Face to escape once more and take the twins hostage, as he erroneously believes them to be conceived by Janus using an experimental fertility drug. The end of the book reveals a surprise twist; Batman learns from Gilda that Janus is not the father of Gilda's twins—Two-Face is. Some of his sperm had been frozen after a death threat had been made against him, and she used some of it to get pregnant. Batman uses this information to convince Two-Face to free the twins and turn himself in.

In the Batman: Hush storyline, his face is repaired once more via plastic surgery. This time around, only the Harvey Dent persona exists. However, he takes the law into his own hands twice: once by using his ability to manipulate the legal system to free the Joker, and then again by shooting the serial killer Hush. He manipulates the courts into setting him free, as Gotham's prosecutors wouldn't attempt to charge him without a body.

In the Batman story arc Batman: Face the Face, that started in Detective Comics #817, and was part of DC's One Year Later storyline, it is revealed that, at Batman's request and with his training, Dent becomes a vigilante protector of Gotham City in most of Batman's absence of nearly a year. He is reluctant to take the job, but Batman assures him it would serve as atonement for his past crimes. After a month of training, they fight Firebug and Mr. Freeze, before Batman leaves for a year. Dent enjoys his new role, but his methods are seemingly more extreme and less refined than Batman's. Upon Batman's return, Dent begins to feel unnecessary and unappreciated, which prompts the return of the "Two-Face" persona (seen and heard by Dent through hallucinations). In Face the Face, his frustration is compounded by a series of mysterious murders that seem to have been committed by Two-Face; the villains KGBeast, Magpie, The Ventriloquist, and Orca are all shot twice in the head with a double-barreled pistol. When Batman confronts Dent about these deaths, asking him to confirm that he was not responsible, Dent refuses to give a definite answer. He then detonates a bomb in his apartment and leaves Batman dazed as he flees.

Despite escaping the explosion physically unscathed to a motel, Dent suffers a crisis of conscience and a mental battle with his "Two-Face" personality. Although evidence is later uncovered by Batman that exonerates Dent for the murders, it is too late to save him. Prompted by resentment and a paranoid reaction to Batman's questioning, Dent scars half his face with nitric acid and a scalpel, becoming Two-Face once again. Blaming Batman for his return, Two-Face immediately goes on a rampage, threatening to destroy the Gotham Zoo (having retained two of every animal - including two humans) before escaping to fight Batman another day.

On the cover of Justice League of America vol. 2 #23, Two-Face is shown as a member of the new Injustice League. He can be seen in Salvation Run. He appears in Battle for the Cowl: The Underground, which shows the effects of Batman's death on his enemies. In Judd Winick's Long Shadow arc, Two-Face realizes that there's another person under the cowl. He hires a teleporter and manages to infiltrate the Batcave. When the new Batman investigates the cave, he is ambushed by Two-Face with tranquilizer darts, and in a hallucination he sees Dent in a red and black Two-Face themed Batman costume. However, Alfred Pennyworth saved the hero from Two-Face's torture after he subdues his accomplice, and with his help Batman convinces Two-Face that he is the real, original Darknight Detective. In Streets of Gotham, Two-Face has been at odds with Gotham's latest district attorney, Kate Spencer, also known as the vigilante Manhunter. Two-Face has recently been driven out of Gotham City by Jeremiah Arkham.