An Arkham Asylum psychiatrist, who begged and eventually convinced her superiors to treat the Joker; Dr. Harleen Quinzel became obsessively fixated on her patient and believed herself to be in love with him. She helped him escape from confinement and took on her own criminal identity as Harley Quinn. Harley was a violent and unpredictable felon whose only motivation, beyond general mayhem, was achieving the Joker’s approval. Because of the Joker's cruel and mercurial nature, this in some ways made Harley just another one of his victims - albeit a very dangerous one.

Before Arkham Origins Incident

During her early life, Harleen had a complicated relationship with her criminal father who gave her distorted morals, but also led her to become fascinated by the extreme criminal mind. She had also been to church on occasion, but often slept through the services. Being academically intelligent, she undertook a psychiatric medical degree at Gotham University as this was the quickest method of being able to treat criminal behavior in institutions such as Arkham Asylum. While at the university, Harleen may have developed her skills in gymnastics, which accounted for her acrobatic abilities displayed later in her life as Harley Quinn.

Arkham Origins Incident

To become a fully qualified psychiatrist researching extreme personalities, Harleen trained under the psychiatrist, Dr. Hugo Strange as part of the psychiatric team at Blackgate Prison. At one point, she, under Strange's orders, contacted one of his patients, Alberto Falcone, the heir to The Falcone Crime Family, to notify him that he had missed his past two appointments, and gave the subtle, but clear threat that Strange and Quinzel would tell his father, Carmine Falcone, about Alberto carrying potentially untreated psychological issues if he didn't continue his appointments.

By the time of Christmas Eve, Quinzel was nearly finished with her psychiatric residency at Blackgate. After Julian Gregory Day, also known as the serial killer Calendar Man, was arrested by the GCPD with the anonymous help of Batman, Quinzel did a psychological evaluation of the serial killer, and determined that Day was insane and thus could not be executed. However, Warden Joseph had her redo the evaluation under the pretense that he was manipulating her (although, it was heavily implied that Joseph himself was being manipulated by Commissioner Loeb into having Day ruled sane and execute him to gain political points). She did so under the condition that she be allowed to do psychiatric evaluation on all new prisoners from that point onward. Harleen appeared when Joker got captured by the GCPD at the Royal Hotel and was sent to Blackgate, where she performed a psychological assessment on him, by using assessments such as word association. During their session, Joker described the encounter between him and Batman and stated that it had changed the way he thought, but he never specified that he was talking about Batman. Harleen therefore thought that Joker was talking about her, so, she grew an affinity toward her patient. 

Harleen was seen again at the Blackgate Riot later that night where she was held hostage by a group of ten escaped Blackgate Prisoners in the Nexus. Batman quickly intervened, but Quinzel showed no form of gratitude toward her savior, nor did she show signs of shock from being almost killed. When Batman asked Quinzel if she was alright, she replied: "What's it to ya?" Harleen walked away from Batman as he stated that: "You were almost killed." She then replied back: "Eh, occupational hazard." And revealed that the Joker was located inside the Panopticon, and that he was waiting for Batman's arrival.

Harleen was seen for the last time with a group of guards escorting the Joker to a cell at Blackgate, who laughed at Batman's deception. As Harleen walked alongside him, Joker stated his belief that his future battles with Batman would indeed be "fun" - possibly already set on the idea of the prison takeover attempt during the Arkham Origins Blackgate Incident three months later. The increasing level of visits would culminate in an attempt to smuggle a can of spray cheese into his cell. Arkham Origins Blackgate Incident

Three months later, Joker, Black Mask and Penguin all broke out and took over the different sections of Blackgate. Thankfully Harleen wasn't on duty when the prison fell to chaos, but she had already developed a soft spot for the Joker; in her notes she called him Mr. J. Following the recapture of all three crime bosses, Harleen was able to return to work as an official doctor.

Arkham Shadow Incident

Harleen continued to treat patients with understanding and empathy, being one of the only two psychiatrists at Blackgate, alongside Jonathan Crane. Thankfully, Warden Joseph was fired after the two breakouts; allowing her to work without manipulation. Harleen began having group therapies to help under childhood issues that shaped inmates.

Unfortunately, thanks to TYGER brutality and Crane forcibly taking her patients for his experiments into understanding the id/shadow, Harleen was not very pleased with her work. She kept trying to help everyone she could, including Arnold Wesker. When Batman arrives, she worked with him and learned Crane was using a chemical on the patients against their will in order to force them to face their shadow. Crane had stymied her work, even going as far as to take steps to deny access to her most fascinating subject: Patient ARK119805. Presumably, Harleen reported Crane to get him fired.

Between Arkham Shadow and Assault on Arkham Incident

Harleen eventually interned at Arkham Asylum after it had been fully renovated. There, she underwent employee orientation with Dr. Gretchen Whistler and was given a permanent office located on the Medical Facility's lower floor: the Secure Access Corridor. There, Harleen continued her work as a criminal psychiatrist and assigned herself to psychologically assess and treat the Joker after previously experiencing his behavior first-hand at Blackgate. Over the course of the Interview Tape Sessions with the Joker, he recognized Harleen's affinity for him, and he was able to easily manipulate her by complimenting her, giving her a flower, and victimizing himself. Harleen was also oblivious to the fact that she had overestimated her abilities to treat the Joker and did not anticipate how manipulative he was, so she did not see that the Joker was in fact using her. She therefore began to strongly empathize for him and believed Batman to be the criminal instead. As revealed in the Spirit of Arkham's 19th deciphered message, her affection toward the Joker had developed to the point where she kissed the glass on the cell which he was locked in, which resulted in Warden Sharp considering performing a lobotomy on her after he killed Joker.

As a result of the Joker's grooming of her own distorted morals, Harleen eventually fell in love with her patient, which was evident by the posters found in her office at Arkham Asylum. Following Joker's orders, Harleen smuggled bombs into the penitentiary to break into his cell and free him. Wearing her trademark jester costume, Harleen introduced her 'new' persona to the Joker and assumed her own criminal identity as 'Harley Quinn'.

Harley spent years serving as the Joker's sidekick and girlfriend. Although she served him faithfully, the Joker often used her as a hostage to escape Batman or as a scapegoat. Despite this, Joker kept her around because of her importance in the execution of his plans and used her to amuse himself, unable to acknowledge his own affection for her. Harley also gained two pet hyenas Bud and Lou.

At one point, she and Joker were invited to the Iceberg Lounge, so to boost the club's reputation. However, a clumsy waitress spilled a drink on Joker, making him melt the poor girl's face with acid from his flower. From this point on, Penguin banned them from the club. Perhaps as an act of revenge, they stole a trunk full of cigarettes from Penguin and crashed it into the river just for a laugh at his expense.

Harley eventually became good friends with Poison Ivy, who she nicknamed "Red." Through this friendship, Harley had her immune system strengthened by Ivy, making Harley immune to most toxins. Harley and Ivy would often make each other laugh after having some beers. They even did a heist, where they stole diamonds and stored them away in a safe. They shared secrets with each other, most of which we're not appropriate to be told to minors. They also worked together with Catwoman at one point, becoming known as the Gotham Sirens.

Eventually, during one of their getaways from the Batman, Harley was kicked out of their getaway car by the Joker to distract Batman. Harley was left badly injured, but alive. From this experience, Harley became resentful towards the Joker, but remained madly in love with him, nonetheless. She spent some time recovering in the Arkham medical wing. Sometime before the events of the film, Harley was "drafted" into the Squad by Amanda Waller, who planted a high-explosive nano bomb in the back of her neck. She was forced onto numerous missions, with an ever-changing crew as they either died or had their bombs turned on for disobedience; two other villains she worked with were Deadshot and Captain Boomerang. She was broken out of custody numerous times by the Joker. Harley was released from Arkham Asylum into the custody of the Roosevelt Halfway Home for Abused Women after she presumably broke off her relationship with the Joker. There, she got in a dispute with one of the staff members over an episode of The Looney Tunes Show that ended in the woman getting her ear bitten off by Harley when she took her phone which resulted in Harley being immediately arrested. Rather than being sent back to Arkham, she was released into Amanda Waller's custody. Waking up in her costume, Harley moaned "Ah crap! Not this again!" as Waller had reassembled the group. Harley was intended to play a vital role in a mission into Arkham Asylum, by using her vast knowledge of the facility and its security to guide the group, and to retrieve a memory drive belonging to The Riddler that contained vital information on every potential member of the Squad. When her being in close proximity to her former lover during the mission was called into question by Deadshot, Harley firmly insisted that she and the Joker were done, calling the clown "a jerk." This claim was sarcastically accepted by Killer Frost and the team remained wary of the risk Harley posed in the field.

Harley immediately began flirting with Deadshot in order to manipulate him and gain his trust since he was the team's field leader, also showing her intense disinterest in Captain Boomerang who was attracted to her and jealous of Deadshot. Once assembled, the Squad was dropped into Gotham where they were to make contact with the Penguin at the Iceberg Lounge who would supply the group with the arms necessary for them to fight their way out if necessary. Harley's presence nearly botched the mission then and there due to the Penguin's intense hatred of the Joker.

However, Deadshot was able to spare the group, and more specifically Harley, by pointing out that simply killing them off would ruin Penguin's standing in the criminal underground including his business. Later that night, Harley surprised Deadshot in his room, asking him to help with an "itch" she had. Annoyed, Deadshot pinned her, but decide "oh, what the hell," resulting in them having a passionate night. Harley was sent on a criminal rampage throughout Gotham in search of a doll that she had been looking for when she was caught by Batman.

When Batman failed to gleam any information from Harley regarding Joker's dirty bomb, she was released into police custody and taken back to Arkham. Along the way, Deadshot took out and replaced a guard, which allowed he and Harley to infiltrate the prison under the guise of bringing Harley to her cell, sabotage a breaker box, and allow the divided team to infiltrate the prison. Along the way, Harley and Joker spotted each other. Harley pretended to ignore his taunts but then used the opportunity to take revenge.

Things quickly dissolved as Harley took Deadshot's gun and used it to shoot at Joker, which didn't work as his cell glass was bulletproof, so she continued by taunting him back and then shooting through one of his air-holes into his cell, much to his surprise. Although it nearly killed Joker, frightening and humiliating him as payback, she successfully damaged a wall panel enough for him to break out later on. Harley openly claimed to be finished with the Joker to his face for all to see, saying that she had found "someone new now, someone better." His immediate frown and growl in response to her allowed Harley to see further payback by making Joker jealous. After another taunt from Harley, the guards came down to aid Deadshot whom they still thought was part of their staff and left a rather miffed Joker behind. Aside from their little encounter, Harley's portion of the plan was a success and allowed the other Squad members to break in, and together the three of them let King Shark in with all their equipment.

The group snuck into the monitoring room where they sabotaged the cameras so that no one could know that they were there. Afterwards, the group made their way across Arkham on foot and got into a short fight with the Asylum's security forces whom they easily slaughtered. Once inside the Asylum's Property Room, Harley quickly reclaimed her prized mallet while Killer Frost and King Shark got into a fight with Batman. Narrowly escaping the collapsing warehouse, the group discovered Riddler's Cane that was supposed to have the flash drive hidden inside was empty. A later confrontation with Riddler revealed the real reason for their mission: for Killer Frost to kill Riddler to prevent the secret to dismantling the explosives in the Squad's necks from getting out. Under Riddler's instruction, the group made it to the Medical Center to make use of the electroshock equipment there. The group lost two more of its members after Waller detonated their bombs: King Shark since his thick skin kept the electricity from reaching the bomb, and Black Spider since Batman had switched costumes with him during the warehouse incident, which meant that Black Spider was unable to deactivate his explosive. After escaping Batman, the group further dissolved when Harley reunited with an angry and jealous Joker who wanted to kill Deadshot. Despite being slapped by his Pistol, Harley revealed that she had merely been using her fellow Squad members to bust Joker out of Arkham. As Joker started to walk away with Harley by his side, he then stopped, turned back around, and pointed his gun at Deadshot. As said by Joker himself, he didn't like people "touching his stuff." But Deadshot used quick thinking to trick the Joker into wasting ammunition, and after a punch to the face, both Joker and Harley fell down the laundry chute while Deadshot reclaimed his firearm.

After the two escaped down the laundry chute, Joker activated the dirty bomb that was hidden inside Harley's mallet, which she had in fact been keeping safe for her lover and lied about to Batman. The two made their way to the Asylum's control room where they unleashed all the inmates to create enough of a diversion to escape. The two stowaway on an SCU Helicopter that Deadshot had already hijacked, and together, the three fought for control over Gotham while the bomb counted down.

The trio crashed into a skyscraper where Deadshot and Joker intensely fought one another while Batman fought an angry Harley, and after he successfully knocked her out, dismantled the bomb. Harley was sent back to Arkham without Joker who was thought dead after the fight against Deadshot. But Waller later stated that in the end, they never found the Joker's body. Deadshot survived his beatdown by the Joker, was reunited with his daughter in the end, and was heavily implied that he shot at Waller with his Sniper Rifle.

A Matter of Family Incident

Used her original name and profession as a therapist, Harley and the Joker manipulated a grieving oil baron, who had built an Amusement Park for his dying daughter as per Harley's suggestion, into and taking over the park after his daughter had died. Joker and Harley then kidnapped Commissioner Gordon and his colleagues, held them hostage there, and threatened to kill him if Batman were to showed up. Batgirl and Robin arrived at the amusement park to thwart the Joker. Harley frequently made comments about Batgirl on the intercom, and gave orders to Joker's Henchmen. Harley made comments to Batgirl when she scanned the park, when she was at the Ferris Wheel saving the guards, when she was defusing the first bomb and when she was at the Merry Go Round. Some comments were encouraging to Batgirl because she was a strong woman, but others were comparisons to Batman saying that Batman would do things faster and better.

When Robin and Batgirl finally got to the Joker, Harley and an army of henchmen started a fight with them. Harley used her Baseball Bat, but her fighting technique was worse than in Arkham Knight, since they were sluggish and could be interrupted with any attacks. Working together, Batgirl and Robin defeated them, and freed the Commissioner. Joker took Harley hostage so he could escape, and Harley was arrested.

Before Arkham Asylum Incident

Harley remained imprisoned in Arkham for some time, though the Joker later helped her escape. She called Dr. Young's office on his orders, acting as secretary to "Jack White." With the help of Joker's inside man Frank Boles, Harley was able to sneak back in Arkham without anyone noticing.

Harley made her way to Bane's holding room in order to sedate him. The reason for this was to keep him quiet when the "visitors" arrived.

With the prep work ready, Harley went to a control room to wait for the Joker's arrival. Once he was there, she would release their henchmen to takeover the island; then they would force Dr. Young to reveal where Titan was being produced, so they could build their army of Banes.

Arkham Asylum Incident

While Batman and the security guards escorted the Joker through the Intensive Treatment Center of Arkham Asylum, Harley was already in the security control room waiting for his signal. As the Joker broke free, she opened the adjacent security field which allowed him to escape Batman and implemented his takeover of Arkham Asylum. Per the plan, Harley began releasing their thugs from all levels of the Asylum. Harley then took Warden Sharp hostage, took possession of his decorative cane as well as wore his Warden Identification Card, and contacted Batman on the monitor. She claimed that the Joker was now in charge of the island and that she was substituting for Sharp as Warden. She also told Batman that Joker was having a homecoming party with Batman as the guest of honor. Batman gave Harley one chance to surrender, which she refused before she smashed her monitor with Sharp's cane, which cut off the feed.

When Batman made his way to the elevator shaft in Secure Transit, Harley appeared, and stated that Joker didn't need to see Batman just yet. Harley proceeded to blow up the elevator cord, which caused the elevator to crash to the floor below and sent herself to the top, and nearly killed a security guard named Henry Smith had Batman not saved him. Harley then regrouped with Frank Boles, who had taken Commissioner Gordon hostage. She and Boles proceeded to secure the front entrance of the Intensive Treatment Center and fought off the guards with an army of Blackgate Prisoners. When Joker found out that Batman was tracking Boles via the alcohol in his breath, Harley was ordered to kill him. With this done, she left him behind, strapped to a gurney with a "Dead End" sign on him. Harley, with Gordon, made her way to the Batmobile first, and ordered her goons to break into it. She then proceeded to the Medical Facility, sat in the main entrance with Gordon tied to a bench by her, and relaxing during her "me time."

Batman eventually tracked Gordon to the entrance and found Harley humming to herself, but was unable to reach her due to an electric security gate blocking the entrance. Spotting Batman as he walked in, Harley told him to scram. He asked where Gordon was, to which she replied: "Wouldn't you like to know?." Gordon then shouted to Batman, and Harley told him to shut up and threw a glass mug at him. Gordon called Harley a "crazy bitch," and Joker contacted Harley via monitor. He yelled at her, and she squealed in a startled tone. Joker asked why Batman was at the Medical Facility, as it was "too early." Harley apologized, kissed Joker through the monitor, and asked him not to be angry with her. He then said: "You little minx! I could never stay mad at you!" and turned off the monitor. Harley said that Batman needed to find another way in, bade him farewell, and cartwheeled out of the room.

On the Joker's orders, Harley proceeded to take Gordon to the Experimentation Chamber, where Bane was being held. Harley was ordered to guard Gordon, and kill him if any of the men patrolling the room spotted Batman. To buy time to set this up, Scarecrow was released to distract Batman. Harley taunted Gordon, telling him that once he and Batman were dead, the Joker would marry her. However, things didn't go as planned; Batman evaded being seen and knocked out Harley by crashing through the ceiling.

Left alone, Harley woke while Batman was busy fighting off a Titan- powered Bane. She promptly escaped back outside. Harley recorded a message for one of the Joker's fake patient sessions with Batman at the Visitor Center, taunting and insulting the Dark Knight. Following her orders, Harley returned to where she had left Sharp, for more of the Joker's insanity. As Batman managed to save Dr. Young from Zsasz, Harley was sent to deal with them; she remained unaware that the Joker had booby-trapped the safe with the Asylum's codes. By the time she arrived, Young was dead from the blast and Batman was out-cold. As Batman woke, Harley joked that Young deserved her death as Joker hated "squealers."

Harley removed the tape on Sharp's mouth, allowing him to insult her. She smacked him with his own cane in return, breaking the jewel off of it. Amused, she tells Batman that "that old looney thinks he runs this place," taking Sharp away for more torture.

Harley left four goons to take Batman to 'the party', but he defeated them and used the Warden's DNA traces from his severed cane tip to follow her. Harley then made her way to the Penitentiary with the Warden, and forced him to read a variety of threatening statements written by Joker over Arkham Asylum's intercom system and tortured him when he hesitated and insulted her.

Harley lead Batman on a goose chase in the Penitentiary. In the Decontamination Room, Harley had two guards strung up and ready to be gassed with Smilex. However, Batman freed them both and got them out of the room before the gas could go off. Eventually, she manged to trick Batman into the Security Control Room, where she had locked up Sharp. Batman saw Harley on a nearby monitor, passing by Poison Ivy's cell. Despite not being on 'Joker's Party List', Ivy convinced Harley to let her free since they were friends. As Ivy happily strode away and blew Harley a kiss, Harley sighed and said: "She's a good kid."

Batman followed Harley and surpassed a variety of her traps until there were a few goons left standing. Harley even electrified the pacification system on the asylum floor to the maximum power to stop his advance, and electrocuted a security guard as a demonstration. Harley then flips up to the vent and taunted Batman and said “Won’t be easy trying to catch me” and blew him a kiss and ran away. Batman eventually got past this obstacle and fought his way through the remaining Blackgate Prisoners and escaped Arkham Lunatics before the fifteen remaining thugs attacked Batman in Extreme Incarceration.

After they were defeated, Joker decided that Harley had failed him, and removed her from the 'party list', much to her annoyance. Out of anger, Harley exited the room and used her acrobatic skills to attack Batman, but was simply thrown aside. Batman then took Harley's 'party list' and Harley tried to punch him. But Batman flipped Harley over, scanned her hand, and acquired her fingerprints. Batman then proceeded to lock up Harley in an adjacent cell, and she accidentally revealed the Joker's location at the Botanical Gardens and claimed that he would rescue her. Batman left Harley crying alone in her cell, getting nothing but insults.

After walking into a nearby room to examine a Glowing Green Trophy placed there by Riddler, Batman became trapped inside after a set of bars slid over the doorway. Harley then taunted him: "The stupid bat has fallen into my trap!", which suggested that she had the Riddler place the trophy in there to trap Batman. Batman used Explosive Gel to destroy the wall above the cell and climbed out back into the cell block, which prompted a shocked Harley to give a violent start and demand: "What? How did you get out of there!?" It could be safely assumed that Harley was escorted back to her usual cell by the surviving Arkham staff upon the Joker's defeat and recapture.

Outfit

The Arkham Asylum rendition of Harley's costume was similar to that of a nurse, with a red, white, black and purple color scheme. Her hair was in the twin ponytails that was most common, albeit without the black and red dye. Harley had a large amount of makeup, as her face was entirely white, with pink blush and red lipstick. This version included a mask, as well as the name tag of Quincy Sharp. Her clothing consisted of a white shirt, with a purple and red corset over it, as well as a black choker necklace. She had gloves that ended above the elbow, which were both red and purple, albeit in opposite order. Harley had a small gap between her top and skirt, which showed her navel. Her belt was a thick black leather one, with a gold square buckle. Her skirt was white and had what appeared to be blood on it. There was a gap between Harley's skirt and boots, in which her fishnet stockings were able to be seen. The boots she wore were leather in appearance, with a purple one on the left, and red on the right. On the bottom of her boots were thick platforms. This appearance has received a largely negative response from both fans and critics due to its extreme departure from Harley's previous looks.