JAG star David James Elliott has signed on to play big-screen icon John Wayne in the upcoming biopic Trumbo, which follows the life of blacklisted Hollywood screenwriter Dalton Trumbo.

Bryan Cranston is portraying the title character, who was one of the 10 writers blacklisted from the Hollywood studio system after he refused to testify before the House Un-American Activities Committee (HUAC) in 1947. He continued to write screenplays under pseudonyms, winning Oscars for writing Roman Holiday and The Brave One.

John Wayne was one of the most conservative actors in Hollywood, who served as the president of Motion Picture Alliance for the Preservation of American Ideals for four years, an organization that helped provide Congress the names of those working in Hollywood who were deemed either friendly or unfriendly. Peter Mackenzie has also joined the cast as the liberal attorney for the blacklisted writers, known as the Hollywood 10. Rounding out the supporting cast are Diane Lane, Helen Mirren, John Goodman and Michael Stuhlbarg.

Jay Roach is directing from a screenplay by John McNamara, with production scheduled to begin next month in New Orleans.

David James Elliott is best known for playing Harmon "Harm" Rabb Jr. for 10 seasons on the hit CBS series JAG. He recently starred in the Fox pilot Welcome to the Family opposite Jane Kaczmarek, and he also had an arc on AMC's Mad Men earlier this year.