It wasJokers day at theToronto International Film Festivalon Monday.

The film traces Arthur Flecks journey from lonely, misunderstood, mentally ill outsider to a domestic terrorist.

Its adark, provocative film in other words.

Joker

Credit: Niko Tavernise/Warner Bros.

Out of Venice, it proved polarizing.

Immediately after the act of it, someone in the Roy Thomson audience enthusiastically cheered.

It was a jarringly light and sunny segue that began while the end-credits were still rolling.

Robert De Niro, Todd Phillips, Joaquin Phoenix, Zazie Beetz and Bradley Cooper

Amy Sussman/Getty Images

(No questions about the films unsettling real-world echoes were asked.)

Honestly I didnt fing know, Phoenix said of when he first signed on.

It started becoming something more than I couldve anticipated.

It was one of the best experiences of my career.

He brought it around to Phoenix.

I would do anything with him, Phillips said.

I want him to be inHangover 4.