Although Gotham doesn't officially return until January, Fox's Batman prequel crops back up to deliver a Halloween message from "Mr. J," the deranged Jeremiah Valeska.

The teaser features footage of the psychopathic Jerome Valeska and his twin Jeremiah, both played by Cameron Monaghan, as the latter explains what differentiates the two: "I showed a proficiency for maths and design, and Jerome, mainly the mutilation of alley cats."

RELATED: Gotham Casts Jim Gordon's New Nemesis For Final Season

With Jeremiah dead and Jerome driven insane by exposure to chemicals, Gotham's new -- if not necessarily true -- Joker was born, and cut a path of destruction through Gotham City that laid the groundwork for the drama's upcoming fifth, and final, season.

The 12-episode final season will not only introduce Batman foe Bane, it will see David Mazouz's young Bruce Wayne embrace his destiny as the Dark Knight. And, yes, viewers will at long last get to see the iconic suit.

RELATED: Gotham: New Close-Up Look At Shane West As Bane

Returning Thursday, Jan. 3, on Fox, Gotham stars Ben McKenzie as James Gordon, Donal Logue as Harvey Bullock, David Mazouz as Bruce Wayne, Robin Lord Taylor as Penguin, Camren Bicondova as Selina Kyle, Erin Richards as Barbara Kean, and Sean Pertwee as Alfred Pennyworth.