NBC Alec Baldwin is reportedly playing Thomas Wayne, Batman's father, in "Joker." According to The Hollywood Reporter, the role is inspired by Donald Trump. "Joker" also stars Joaquin Phoenix as the Joker, Robert De Niro, Zazie Beetz, and Marc Maron. Baldwin is reportedly joining the cast of next year's "Joker," an origin story about Batman's greatest enemy, as Thomas Wayne, who is Batman's father. Story details about "Joker" are scarce, so it's unknown how deep into Batman lore the movie will go.