(CNN) — "Joker" was made for Joaquin Phoenix.
Warner Bros. debuted the official trailer Wednesday for the comic book film. Playing the notorious Batman villain, Phoenix inhabits the role so completely he's almost guaranteed to get noticed during Oscar season.
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The film takes place in 1981 and tells the backstory of Arthur Fleck, a failed stand-up comedian who turns to murder in Gotham City.
Set to Nat King Cole's "Smile," the trailer shows Phoenix working as a failed sign-holding clown on the streets.
"My mother always tells me to smile and put on a happy face. She told me I had a purpose to bring laughter and joy to the world," an unhinged Phoenix says before getting attacked.
The studio released a first look for the movie in April.
"The Hangover" director Todd Phillips helms the project.
Robert De Niro plays a talk show host who sparks the Joker's downward spiral when he disses him on TV. "Atlanta" star Zazie Beetz plays Phoenix's love interest. Frances Conroy, Bill Camp and Marc Maron also co-star in the film.
"Joker" is set to premiere at the Venice Film Festival, becoming the first comic book movie to do so, then will play at the Toronto International Film Festival and the New York Film Festival.
"Joker" officially hits theaters on October 4.
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