Writer Mark Boal accepts the Writers Guild Award for Best Original Screenplay onstage at the 2013 WGAw Writers Guild Awards on Feb. 17, 2013, in Los Angeles. / Getty
The CIA thrillers "Argo" and "Zero Dark Thirty" both won top screenplay honors from the Writers Guild of America Sunday at the 65th Writers Guild Awards in Los Angeles.
The guild's adapted screenplay award went to Chris Terrio for "Argo," director Ben Affleck's tale of the CIA's daring masquerade of six U.S. diplomats as a Hollywood film crew to rescue them from Iran during the hostage crisis there.
Mark Boal won the prize for original screenplay for "Zero Dark Thirty," director Kathryn Bigelow's chronicle of the CIA's manhunt for Osama bin Laden.
Director Malik Bendjelloul won the documentary award for "Searching for Sugar Man," his portrait of acclaimed but largely forgotten 1970s musician Rodriguez.
The guild was the last of Hollywood's major trade unions to weigh in on the year's top films before next Sunday's Academy Awards ceremony.
"Argo" has emerged as the best-picture favorite for the Oscars after sweeping top prizes at earlier film honors, including the Golden Globes along with awards from the Directors Guild of America, the Screen Actors Guild and the Producers Guild of America.
Among the guild's TV winners: