Filmmaker Martin Scorsese opened up about working on his upcoming directorial Killers of the Flower Moon and added how it was important to spend time with Osage people.

Expected to be a crime drama, the film is set against the backdrop of the early 1920s and about the murders that took place after major oil deposits were discovered on the tribe's land.

"We tried to do right by them as much as we could. We shot in the actual location, even the doctor's office,” the director said when he was interviewed by Leonardo DiCaprio, at the recently held CinemaCon.

"It wasn't an easy film to make. I am a New Yorker, and there were prairies out there. Wild horses. Coyotes,” he added.

Killers of the Flower Moon stars Leonardo DiCaprio, Robert De Niro, Lily Gladstone, Jesse Plemons, Cara Jade Myers, JaNae Collins, Jillian Dion and Tantoo Cardinal.

Directed by Scorsese and written by the filmmaker along with Eric Roth, the film is based on David Grann’s bestselling book of the same name Killers of the Flower Moon. The film is set in 1920s Oklahoma and shows the serial murder of members of the oil-wealthy Osage Nation, a string of brutal crimes that came to be known as the Reign of Terror, according to Apple TV+ note.