Dr. Harleen Quinzel was a psychiatrist interning at Arkham Asylum, having been fascinated in studying The Joker. During their sessions, Quinzel fell in love with the Joker, breaking him out of Arkham several times and having her psychiatric license revoked. She would then re-invent herself as Harley Quinn, sidekick and lover of the Joker. Besides the Joker, Harley Quinn also works with Poison Ivy whom she is close friends with. She is a skilled gymnast as well as having psychiatric knowledge and, because her friendship with Ivy, an immunity to toxins as well. In Lego Batman: The Video Game she is a supervillain and follower of the Joker. In the game she has the ability to walk a tightrope, super-jump, and bypass security for all levels with guards in security booths.