Exclusive: Scoot McNairy has joined the cast of Warner Bros.’ “Argo,” directed by and starring Ben Affleck.McNairy joins a cast that includes Bryan Cranston, John Goodman and Alan Arkin. Chris Terrio is adapting Joshuah Bearman’s April 2007 Wired magazine article “How the CIA Used a Fake Sci-Fi Flick to Rescue Americans from Tehran,” which tells how the CIA and the Canadian government teamed to recover six U.S. diplomats who’d been taken hostage in 1979. George Clooney and Grant Heslov are producing through their Smokehouse banner along with David Klawans and Affleck. McNairy recently wrapped production on “Cogan’s Trade” with Brad Pitt . He is repped by ICM and The Group.