Title: Harley Quinn (TV series)
Content: Charlie Adler as Nick Quinzel, Grandpa Quinzel ; Chris Diamantopoulos as Aquaman ; Susie Essman as Sharon Quinzel, Grandma Quinzel ; Meryl Hathaway as Marcus ; Jameela Jamil as Eris ; Tom Kenny as Clayface's Hand ; George Lopez as Himself ; Justina Machado as Bethany ; Howie Mandel as Himself ; Natalie Morales as Lois Lane ; Brad Morris as Victor Zsasz ; Frankie Muniz as Himself ; Suzy Nakamura as Realtor ; Rhea Perlman as Golda ; Jonah Platt as Clayface (singing voice) ; Scott Porter as The Flash ; Nicole Sullivan as Mrs. Cobblepot, Benjamin ; Talia Tabin as Debbie Day ; Jessica Walter as Granny Goodness, Wendy Brown ; Mark Whitten as Herman Cizko / The Cowled Critic 
Title: Harley Quinn (DC Extended Universe)
Content:  Dr. Harleen Frances Quinzel, later known as Harley Quinn, is a fictional character in the DC Extended Universe, based on the character of the same name from DC Comics. Portrayed by actress Margot Robbie, she first appears in film in Suicide Squad, playing a major role, and also stars in Birds of Prey and The Suicide Squad. She is first depicted as Joker's psychiatrist in prison, then later his lover and partner in crime, before going off on her own misadventures in her DCEU appearances. Her introduction sequence in Suicide Squad mentions her as an accomplice and directly responsible for the murder of Batman's sidekick Robin. Robbie's portrayal of Harley Quinn has received widespread critical acclaim.
Title: Characters of the DC Extended Universe
Content:  Dr. Harleen Quinzel (portrayed by Margot Robbie) first appears in Suicide Squad as an upcoming psychiatrist who works with the Joker, falling madly in love with him and being swayed to insanity and a life of crime by the "Clown Prince" of crime. Picking up the moniker Harley Quinn, she and Joker terrorize Gotham City until she is apprehended by Batman. She is later recruited by Amanda Waller along with Deadshot and other criminals into Task Force X, also known as the Suicide Squad, before Joker breaks her out. Birds of Prey explores Harley's misadventures and personal development after she breaks up with Joker, while The Suicide Squad sees her re-incarcerated and sent on another mission with a later roster of the Suicide Squad. Harley's character arc in the films sees her go from being defined by her abusive relationship with Joker to becoming more independent and willing to help society, despite her malevolent tendencies and chaotic, unpredictable personality. Robbie stated that it took three hours to prepare her hair, makeup and costume for the role and "at least 45 minutes" to take it off.
Title: Harley Quinn
Content:  Harley appears in the DC Universe Online video game, with Arleen Sorkin returning as her voice. Harley is the basic Legends PVP character granted to Villains without having to spend Marks of Legend. To date, this was the last time Arleen Sorkin voiced the character;, Harley Quinn is now voiced by Jen Brown, starting with a DLC episode based on the Gotham City Sirens.
Title: Harley Quinn
Content:  DC Comics' publishing line, behind Superman, Batman, and Wonder Woman. Originally voiced by Arleen Sorkin in the DC Animated Universe, she has since appeared in many other DC projects voiced by actresses such as Tara Strong, Hynden Walch, Laura Bailey, Jenny Slate, Melissa Rauch, Laura Post, and Kaley Cuoco; the latter provided the character's voice in the 2019 animated series, Harley Quinn. Mia Sara portrayed the character in the 2002 television series Birds of Prey. Harley Quinn makes her live-action cinematic debut in the DC Extended Universe film Suicide Squad (2016), where she is portrayed by Margot Robbie. Robbie reprises her role in Birds of Prey (2020) and The Suicide Squad (2021).
Title: Harley Quinn
Content: In 2002, a short-lived television series, Birds of Prey, included Harley Quinn as a psychologist and the main antagonist, portrayed by actress Mia Sara. In this show, Harleen Quinzel uses her day job as a psychologist to achieve her hidden purpose: to take control of the city of New Gotham. She does not wear a costume, although she does wear an outfit that is reminiscent of her cartoon costume in the series finale "Devil's Eyes". ; Harley Quinn made a cameo appearance in the Arrow season two episode "Suicide Squad", voiced again by Tara Strong, while physically portrayed by Cassidy Alexa (credited as "Deranged Squad Female"). The series star Stephen Amell revealed in an interview she was originally set to appear in the season two finale episode "Unthinkable", but was cut due to time. The show's 
Title: Birds of Prey (2020 film)
Content: Margot Robbie as Dr. Harleen Quinzel / Harley Quinn: A former-certified psychiatrist, who became a crazed criminal and the Joker's accomplice/girlfriend, and later a part of the Suicide Squad. She has since cut ties with the Joker after the pair broke up. Screenwriter Christina Hodson sought to reinvent Harley, wanting to expand on the character following her departure from the Joker's company. Hodson called Harley the character she enjoyed developing most due to her unpredictable personality. ; Mary Elizabeth Winstead as Helena Bertinelli / The Huntress: A vigilante who is the orphaned daughter of gangster Franco Bertinelli.  Ella Mika portrays a young Helena during flashback scenes. 
Title: Harley Quinn
Content:  its own fun. There are so many moments in that movie that I just think are wonderful. [...] When I saw her running, laughing hysterically, pushing a shopping cart full of Peeps, I said, "That’s my girl." All those little impish things that she did in the movie – sitting down eating cereal, watching Tweety Bird cartoons, and just kind of skipping through life cheerfully oblivious of the devastation she’s caused – that’s Harley." ; Harley Quinn appeared in the film The Suicide Squad (2021), a standalone sequel to Suicide Squad. Margot Robbie portrays Dr. Harleen Quinzel / Harley Quinn in the DC Extended Universe.
Title: Harley Quinn (TV series)
Content:  Alongside the series order announcement, it was reported that the producers of the series were expected to approach Margot Robbie, who portrays the character in the DC Extended Universe, to reprise the role; but this was false. In an interview after the season 1 release, Halpern went on record saying Robbie was kept in the loop, but she was never interested in playing the role since she was filming and producing Birds of Prey at the time. Other characters expected to be featured in the series included the Joker, Poison Ivy, Sy Borgman, Doctor Psycho, Malice Vundabar, King Shark, and Clayface. On October 3, 2018, it was announced that Cuoco would voice Harley 
Title: Harley Quinn
Content: The character debuted in the 2016 film Suicide Squad. Paul Dini, the creator of Harley Quinn, said Robbie "nailed" her role. ; Harley Quinn appears in the 2020 spin-off film Birds of Prey, which Robbie also produced. On Robbie's portrayal of the character in the movie, Dini stated, "I think they really got the essence of the character down, and they made her quite a lot of fun and appealing in so many ways. She’s not totally the animated version, and it’s not totally the Jimmy [Palmiotti] and Amanda [Conner] version, but it kind of borrows from all of them and creates its own reality 

Question: who plays harley quinn?
Answer: Arleen Sorkin.