'Joker' director Todd Phillips has revealed that Joaquin Phoenix, whose unnerving performance film is generating early Oscar buzz, would sometimes walkout from set in middle of a scene.

In a cover story on 44-year-old actor in New York Times, Phillips revealed that y h several fruitful creative differences over character, one of most iconic and complex villains in Batman lore.

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Phillips said Joaquin Phoenix "lost his composure on set, sometimes to bafflement of his co-stars".

"In middle of scene, he'll just walk away and walk out. And poor or actor thinks it's m and it was never m  it was always him, and he just wasn't feeling it," he told New York Times.

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Joaquin Phoenix, however, would always return after taking a break. 

"We'll take a walk and we'll come back and we'll do it," is what Joaquin Phoenix told Phillips after a particularly tense moment.

Robert De Niro, who stars as a late-night show host in movie, was one person that Joaquin Phoenix never walked out on. De Niro said Joaquin Phoenix was a 'consummate professional'.

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"Joaquin was very intense in what he was doing, as it should be, as he should be," De Niro said. 

Phillips is t worried about how Joaquin Phoenix will handle publicity of film, saying, "If he goes on Jimmy Kimmel and walks off after two minutes, I'd be like, That's my boy'. He follows his own rhythm." 

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Watch Joker trailer here: