The Penguin

The Penguin is a crime Lord in Gotham and one of Batman's enemies.

Biography
While attending an art gallery, Dick Grayson wondered what the Penguin was doing.

Season 1

 * "Donna Troy" (mentioned)

Behind the scenes

 * "The Penguin" is the alter ego of Oswald Chesterfield Cobblepot, one of Batman's most well-known adversaries in DC Comics.