First appearing in the DC Universe in 1992, Dr. Harleen Quinzel was on a path to a brilliant career in psychiatry. Working as a psychiatrist at Gotham’s Arkham Asylum, it was here that she came to treat the infamous Joker. The more she worked with his crazed criminal mind, the more obsessed she became with his warped psyche, eventually falling deeply in love with him. Descending into madness, the Joker used her love, mentally manipulating her until she helped him escape from the asylum. It was then that Dr. Harleen Quinzel became notorious as the bubbly psychotic, Harley Quinn. With her athletic training, immunity to toxins, intellectual brilliance and wild unpredictability, Harley Quinn is one of the most compelling and dangerous villains in the universe. The moment for mayhem is now.