New additions to the already loaded cast of Martin Scorsese’s Killers of the Flower Moon are musicians Jason Isbell and Sturgill Simpson. The Grammy-winning recording artists will stretch their acting muscles in the filmic adaptation of David Grann’s novel of the same title that tells the true story of the Osage Nation massacre in 1920s Oklahoma. 

Eric Roth wrote the screenplay about the historic tragedy that has come to be known as The Reign of Terror. The Osage Nation land, rich with oil, became the locale of serial murders and sinister secrets, which a newly formed FBI came to town to investigate. 

Frequent collaborators of Scorsese, Leonardo DiCaprio and Robert De Niro were the earliest announced cast members. Rising star Lily Gladstone and The Irishman alum Jesse Plemons then signed on earlier this year. The growing cast also includes Tantoo Cardinal, Cara Jade Myers, William Belleau, Louis Cancelmi, JaNae Collins and Jillian Dion.

Jason Isbell will play Bill Smith, the nemesis and foil to DiCaprio’s Ernest Burkhart. He marks Killers as his first acting role with a speaking part, previously making a cameo in the 2019 movie-version of Deadwood. Isbell is a singer-songwriter well known for his storytelling abilities. He also fronts the band the 400 Unit and is married to fellow musician Amanda Shires. Isbell, who wrote “Maybe It’s Time” for Bradley Cooper’s character in A Star Is Born has a new album called Reunions coming out this May.

Sturgill Simpson, a beacon of the outlaw country genre, will play bootlegger and rodeo star Henry Grammer. More familiar with the film industry, Simpson’s acting credits include Melina Matsoukas’ Queen and Slim, Jim Jarmusch’s The Dead Don’t Die and Blumhouse Productions’ The Hunt alongside Emma Roberts and Hilary Swank. Among his many accolades is a Grammy win for Best Country Album for his 2017 A Sailor’s Guide to Earth. His Sound and Fury was nominated for Best Rock Album at this year’s Grammys.

Killers of the Flower Moon, an Apple Studios and Imperative Entertainment production, is produced by Dan Friedkin, Bradley Thomas, Scorsese, and Appian Way Productions. Filming is set to begin in May.