William Smillie was a Chicago-born actor best known for his appearances in Chicago-based productions. Smillie trained in improv at iO (Improv Olympic) Chicago, and made his professional acting and feature film debut in "The Dark Knight" (2008). He played a clown mask-toting henchman of the Joker in the film, which was shot in Chicago. That same year, he made his television debut in an episode of "ER" (NBC, 1994-2009). Smillie appeared in the Vince Vaughan and Kevin James movie "The Dilemma" (2011), which was also shot in Chicago, then landed a two-episode part on "The Chicago Code" (Fox, 2011). He played recurring character Hadley on "Chicago Fire" (NBC, 2012-) before joining the main cast of the police procedural "APB" (Fox, 2017).