HARLEY QUINN: Gillian Jacobs (Garden of the Night, Community, Fringe)
I know this may be an odd choice, but I believe Gillian could handle this role. Though she is mainly known as Britta in the Community, which is a comedy, she is also a FANTASTIC dramatic actress. After seeing her work in the drama film, Garden of the Night, I felt she would be perfect. I believe she would be great. Oh, and in Fringe, she played a serial kidnapper...not the most sane person she has played. She would also be good when it comes down to Harley's double sided personality. Both Dr. Harleen Quinzel AND the crazy, Harley Quinn.