Joaquin Phoenix Is "Embarrassed" By His Diva Behavior on Set of Joker

The actor opened up about what it was like to make the movie while chatting with Jimmy Kimmel.

Joaquin Phoenix just got put on blast.

While sitting down with Jimmy Kimmel on Tuesday night's Jimmy Kimmel Live, the actor was surprised by an outtake from his upcoming flick Joker, sent over to the show by director Todd Phillips. The video showed an annoyed Phoenix sniping at the film's cinematographer Lawrence Sher.

Clad in his Joker get-up (green hair, clown makeup), Phoenix is seen telling Sher to stop distracting him. "The constant whispering," he said in the clip. "Just shut the f@*k up, dude. I'm trying to find something real." In response, Sher calls him Cher, poking fun at his diva-like behavior.

"It's not even an insult," Phoenix said of the new nickname. "Cher, really? She's a singer, actor, dancer, fashion icon. How is that a f*!king insult?" He then proceeded to storm off set and away from the camera.

After the short video wrapped, the actor—clearly unaware this would be played—was visibly flustered.

And, he took it upon himself to apologize.

"This is so embarrassing," Phoenix told Kimmel. "Sometimes movies get intense because you're a lot of people in a small space and you're trying to find something, so it can feel intense."

"That was supposed to be private," he continued. "I'm a little embarrassed, I'm sorry about that. I'm sorry you guys had to see that."

Check out Kimmel's full interview with Phoenix to see the uncomfortable outtake, as well as some other interesting tales from the creation of Joker.