Dean O'Gorman, who stars in The Hobbit trilogy as the dwarf Fili, has signed on to portray legendary Hollywood actor Kirk Douglas in the upcoming biopic Trumbo.

Bryan Cranston is starring as Dalton Trumbo, who was one of the highest-paid screenwriters in town during the 1940s and early 1950s. He became one of the blacklisted writers known as "The Hollywood 10" when he refused to testify in front of the House Un-American Activities Committte (HUAC), forcing him to write under pseudonyms for several years.

Kirk Douglas both starred in and executive produced the 1960 epic Spartacus, where he hired Dalton Trumbo to write the script, and gave him credit under his own name. That gesture helped destroy the negative stigma placed on the blacklisted writers. The supporting cast also includes Helen Mirren, John Goodman, Diane Lane, Michael Stuhlbarg, David James Elliott and Peter Mackenzie.

Jay Roach is directing from a screenplay by John McNamara, with Michael London producing through his Groundswell Productions company. Shooting is currently under way in New Orleans.

Dean O'Gorman will close out The Hobbit trilogy in December with The Hobbit: The Battle of The Five Armies.