After announcing that Suicide Squad stars Harley Quinn and Killer Croc would be making their way to Gotham’s third season
, executive producer Ken Woodruff says Quinn might turn out to be someone who has already been on the show. Hmm. It’s going to take the brilliant analytical mind of the Riddler to figure this mystery out.
Source: io9 – Gotham Exec Says Harley Quinn Might Have Already Appeared on the Show, Whatever Could They Mean