Joaquin Phoenix seemed to get a surprise last night on the Jimmy Kimmel Live! show when he was confronted with a behind-the-scenes Joker clip capturing him in an expletive-laden rant…Or did he?

In the footage, featuring Phoenix in his Joker character make-up, the actor takes issue with “constant whispering” on the set while he’s “trying to find something real” in his performance. The actor apologizes before becoming aggravated with ‘Larry’ [DoP Lawrence Sher] for apparently comparing him to the singer Cher. He then storms off camera, saying, “I can’t do this man.”

Phoenix cringed and told Kimmel the clip was “embarrassing”: “Sometimes movies get intense. You have a lot of people in a small space and you’re trying to find something,” he said sheepishly. “That was supposed to be private, I’m sorry you guys [the audience] had to see that.”

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“I should probably publicly apologize to Larry. I am sorry, but he did whisper constantly while we’re trying to work, and sometimes it’s really hard to find the emotion you’re after… he shouldn’t have done it,” the actor added.

But the clip and its revelation also played out on the show like a bit. Both Phoenix and Kimmel have prior experience with mocks and skits. In Phoenix’s 2010 mockumentary I’m Still Here, the actor took part in a famously bizarre appearance on Letterman in which he claimed he had retired from acting to focus on music.

In the same interview, Phoenix talked about shedding weight to play the role of Joker.

“It’s difficult at times [losing weight], but there’s also something very empowering about it, having that level of control of yourself. In the beginning you’re exhausted, but once you reach your target weight you start to feel energized and excited,” he recalled

“You can’t watch TV because commercials come on for food. You don’t socialize at all. Food and drink is what all of our social activity revolves around. If you don’t have that, you go ‘what the f**k am I doing?’.”

The actor also discussed the response that his family has had to the film.

“My whole family came to the premiere. Afterwards we went back to my place and my sisters got into a heated discussion about what the movie is about, what it meant, what was real and what wasn’t – it was really fun to watch that,” he said, jokingly adding that they hadn’t seen his other movies.

Kimmel asked if the film was gruelling to make, which Phoenix rejected.

“It was a light set. Todd [Phillips] was really funny. I feel almost guilty but we had a really good time.”

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