April 3 (UPI) -- Joaquin Phoenix dons clown makeup and a purple suit in the first teaser trailer for Warner Bros. and DC Comics' upcoming psychological thriller, Joker.
The clip, released on Wednesday, follows Phoenix as Arthur Fleck, a man who descends into madness after facing multiple hardships on the streets of Gotham City.
Fleck then starts to transform into the iconic Joker -- best known as Batman's greatest foe -- as he begins to take his revenge against society.
"I used to think that my life was a tragedy but now I realize it's a comedy," Fleck says.
The teaser trailer also briefly features stars Zazie Beetz and Robert De Niro as a late night talk show host who invites the Joker onto his program.
Joker, directed by Todd Phillips, is set to arrive in theaters on Oct. 4. Marc Maron, Bill Camp, Frances Conroy, Brett Cullen, Glenn Fleshler, Douglas Hodge Josh Pais and Shea Whigham are also set to star.