Joaquin Phoenix just 'walked away' from 'Joker' sets

Joaquin Phoenix whose performance in 'Joker' has been receiving rave from critics, walked off from the sets of the film after losing his temper a few times.

A New York Times story, cited by Entertainment Weekly, revealed that the 44-year-old actor "lost his composure on the set, sometimes to the bafflement of his co-stars."

"In the middle of the scene, he'll just walk away and walk out," the film's co-writer and director Todd Phillips said.

"And the poor other actor thinks it's them and it was never them -- it was always him, and he just wasn't feeling it ... If he goes on Jimmy Kimmel and walks off after two minutes, I'd be like, 'That's my boy.'"

But the actor never walks out on his most esteemed co-star Robert De Niro, who plays a late-night talk show host in the film.

"Joaquin was very intense in what he was doing, as it should be, as he should be," De Niro said and called the star a consummate professional.

In order to fit well into the shoes of his character, Phoenix, a three-time Oscar nominee, had shed 52 pounds for his role in the dark drama.