About the film
Trumbo is a 2007 American documentary film directed by Peter Askin, produced by Will Battersby, Tory Tunnell, Alan Klingenstein, and David Viola, executive produced by Jim Kohlberg, and written by Christopher Trumbo. It is based on the letters of Christopher Trumbo's father, Dalton Trumbo, an Oscar-winning screenwriter who was imprisoned and blacklisted as a member of the Hollywood Ten, ten screenwriters, directors and producers who refused to testify before the House Un-American Activities Committee (HUAC) in 1947 during the committee's investigation of Communist influences in the Hollywood film industry.
From the film's Wikipedia article (CC BY-SA 4.0).