Quentin Tarantino allegedly warned Brad Pitt he’d “be dead in this business” in a major scolding on the set of 2019’s “Once Upon a Time in … Hollywood.”

Pitt’s co-star Bruce Dern told People, in an interview published Thursday, the incident occurred shooting a scene when Pitt’s character, Cliff Booth, checks on Dern’s character, George Spahn, who is blind.

“When Brad Pitt wakes me up in ‘Once Upon a Time in … Hollywood,’ I’m in the bed and I get up and I’m a little groggy and stuff and I just say, ‘I’m not really sure what’s going on,'” the 89-year-old recalled.

Since he improvised that line, surprising Pitt, Pitt “cut the camera,” which Dern said angered Tarantino.

“The look on Quentin’s face — I mean, he was insanely grave — and he said, ‘Brad, what did you just do?'” Dern remembered.

The famous director, 63, allegedly told Pitt, “Never again in your life will you ever cut a camera or you’ll be dead in this business. That’s my domain.”

Pitt told Tarantino, “Well, that wasn’t in the script what he said,” according to Dern.

For the scene that made the final edit, Dern improvised a different line: “I don’t know who you are, but you touched me today. You came to visit me. Now I gotta go back to sleep.”

The “Nebraska” actor explained to the outlet that he came up with that line after Pitt and their co-star Leonardo DiCaprio expressed their admiration for Hollywood icon Dern.

“They did that, and that touched me,” Dern said.

A source told Page Six, “Quentin is one of Brad’s favorite directors. They have great chemistry and respect for one another.”

Page Six has reached out to reps for Pitt and Tarantino for comment.

In “Once Upon a Time in Hollywood,” Pitt plays the stuntman for Hollywood actor Rick Dalton (DiCaprio), and the role earned him the Academy Award for Best Supporting Actor in 2020.

In his acceptance speech, the “F1” actor praised Tarantino for being “original” and “one of a kind.”

“The film industry would be a much drier place without you and I love the ethos you gave Cliff Booth,” Pitt gushed at the time.

The pair are collaborating again on “The Adventures of Cliff Booth,” the sequel to “Once Upon a Time in … Hollywood,” with Pitt reprising his role from the first film with a script written by Tarantino.

David Fincher is directing the sequel, which comes out in November.