Flash fans have known that Barry’s nemesis, Reverse Flash, would be showing up in the series ever since the pilot. Heavily inspired by the recent comic storyline where Barry fought the Reverse Flash back when his mother was killed (and thus causing Flashpoint/the New 52), the series has been setting up Professor Zoom since day one. While fans have suspected Harrison Wells as being Professor Zoom from the future, the synopsis for the December 9th mid-season finale hints otherwise:
BARRY COMES FACE-TO-FACE WITH THE MAN IN THE YELLOW SUIT/AMANDA PAYS RETURNS TO THE FLASH â€” Barry (Grant Gustin) finds himself face-to-face with his nemesis, the man in the yellow suit, a.k.a. Reverse Flash, who killed his mother. Barry is frustrated when the Reverse Flash escapes, but Dr. Wells (Tom Cavanagh) and Cisco (Carlos Valdes) come up with a plan to trap him. All they need is bait, so they turn to Dr. Tina McGee (guest star Amanda Pays) from Mercury Labs to help. Meanwhile, itâ€™s Christmas at The West household and Iris (Candice Patton) is in full holiday cheer. Eddie (Rick Cosnett) gives her a surprising gift but also leaves her with a question that could change her life. Joe (Jesse L. Martin) joins the search for the man in yellow and ends up in the crossfire. Caitlin (Danielle Panabaker) finds Ronnie (Robbie Amell). Ralph Hemecker directed the episode written by Todd Helbing & Aaron Helbing (#109).
This could lead more strength to the popular fan theory that Wells is actually Barry from the future. Or this could just be a massive red herring and Wells could still be evil. Either way, it looks like The Flash is going to continue to be the best comic-based series on television.