D'Agosto will play idealistic and charming Assistant District Attorney Harvey Dent, who eventually becomes the villain Two-Face. He will recur throughout the rest of the season, with the possibility of becoming a regular in Season 2.
The Fox drama has also added Dexter's David Zayas as mob boss Salvatore Maroni, the man who disfigures Dent and leads to the villainous transformation.
What do you think of the castings?
Gotham airs Mondays at 8/7c on Fox.
Gotham's Robin Lord Taylor on becoming the villainous Penguin: