TV shows about superheroes are all the rage now, with shows like "The Flash," "Arrow," "Agent Carter" and "Agents of S.H.I.E.L.D" enjoying high ratings. The same holds true for Fox's "Gotham."

But what sets this series apart is its focus on a young Det. James Gordon (Ben McKenzie) and the origin stories of some of Batman's greatest villains. Batman himself is still years away from becoming the masked crusader; he is just Bruce Wayne in the series, a young boy grieving for his lost parents.

Fans were introduced to Edward Nygma/The Riddler (Cory Michael Smith), Oswald Cobblepot/Penguin (Robin Lord Taylor) and Selina Kyle/Catwoman (Camren Bicondova) in the first season.  Now, producer Bruno Heller is upping the stakes and introducing more villains in "Gotham's" second season.

Dr. Victor Fries, who is more known as Mr. Freeze, will reportedly be joining the roster of Gotham villains. In the canon, Dr. Fries is a cryogenics scientist looking for a cure for his wife's disease when an accident left him dependent on a cryogenic suit in order to survive. The timeline of his origin story is a little different in the comics so there has been some speculation that the show's writers will tweak his story a bit.

Batman's arch enemy, The Joker, will finally appear in season two. But he is not yet the Joker that has been Batman's bane for years. Instead, Heller said the show will introduce a "pre-embryonic" Joker.

In an interview he gave to Comicbook.com, Gotham's creator said that fans would not have to wait until the end of the season to learn more about the Joker because "the beginning of season two is the very earliest origins of how The Joker came to be."

But not all the new faces are bad. Chris Chalk is on board to play Lucius Fox, Bruce's mentor, business manager and his future ally. Dr. Leslie Thompkins (Morena Baccarin) is also back as Det. Gordon's love interest and fans will also see more of Harvey "Two-Face" Dent (Nick D'Agosto).

The second season of Gotham will reportedly air a bit later in the fall on Fox.