I bet you it was Kelly...sigh. Darkness and Shadow are not themes related to Superman but Batman. This show has had more Batman elements to it in the last two or three seasons than one would expect. It has become dark, gritty, it's always been angsty, you have two of it's major characters involved in arcs of self-doubt, a sidekick, a hero who operates during the night and is clad in black and hangs out with Gargoyles, let's see what else am I missing?