Joaquin Phoenix fainted in a "very intense" scene on the set of his upcoming film Beau Is Afraid, according to its director Ari Aster.
The Joker actor, 48, was shooting a scene with co-star Patti LuPone, 73, when the incident happened.
Speaking at a Q&A panel in New York, the Midsommar director discussed his upcoming film after screening it for the moviegoers.
He explained how Joaquin was off-camera when he collapsed to the floor whist his on screen mum Patti LuPone was shooting her scene.
The forthcoming film was the first time the acclaimed director had worked with the Gladiator star.
"There was a scene that was very intense for Patti and it was a shot that was on Patti, it was not on him and all of a sudden he fell out of frame," he told the panel according to Deadline.
"I was really p**sed cause it was a really good take. It felt confusing so I went around the corner and he was collapsed.
"I knew it was bad because he was letting people touch him and people were tending to him and he was allowing it."
Ari added: "The point is that he fainted in somebody else’s take, he wasn’t on camera and he was helping them, he was in it for them to the point where he collapsed.
"It’s very poetic that he collapsed in somebody else’s shot."
Beau Is Afraid is about "a paranoid man [who] embarks on an epic odyssey to get home to his mother," Deadline reported.
The upcoming motion picture has a cast that includes Nathan Lane, Amy Ryan, Kylie Rogers, Denise Ménochet, Parker Posey, Stephen McKinley Henderson, Richard Kind, Hayley Squires and Michael Gandolfini.
According to IMDB, the film is expected to hit theatres on May 19.
Joaquin has recently been spotted filming scenes for the sequel to Todd Phillip's Joker from 2019 which gained an Oscar nomination for the actor.
Pop icon and actress Lady Gaga has joined the cast as the Clown Prince of Crime's love interest Dr Harleen Quinzel - better known as Harley Quinn.
Gaga sent fans into a frenzy as she was seen walking past a hoard of protesters as the character when one woman shouts "you're going to hell", which stops Harley in her tracks as she turns and kisses the woman on the mouth.
Joker: Folie á Deux is set to hit cinemas on October 4, 2024 - just in time for Halloween.