We learn today who one of the three "mystery" heroes will be. Story by Matt Cummings Those new to the superhero-on-television trend might have forgotten the one that started it all: CW's Smallville , a mix of teenage melodrama in its first 8 seasons, and a fairly good superhero tale in its last two. During those final seasons, we were introduced to the mother of all superhero team-ups, The Justice Society of America, which featured Doctor Fate, elder versions of The Flash and The Green Lantern, and Michael Shanks as the nearly-immortal Hawkman. Hidden within the epic "Absolute Justice" was Hawkman's origin story, featuring the story of his dead love, Hawkgirl. Fast forward one disappointing series finale and two very successful - and frankly better - series in The Flash and Arrow , and we've arrived at a sort of full circle. For it was revealed today by Deadline that one of three "mystery heroes" has been cast in the team-up ...