Homeland is an American drama-thriller television series developed by Howard Gordon and Alex Gansa based on the Israeli series Hatufim. It premiered in 2011 and was produced by Teakwood Lane Productions, Cherry Pie Productions, and Keshet Broadcasting for Showtime. The series focuses on Carrie Mathison, a CIA officer dealing with bipolar disorder who suspects Marine Sergeant Nicholas Brody was turned by al-Qaeda while in captivity. Other main characters include Saul Berenson, Carrie's mentor at the CIA, and Director of the Counterterrorism Center David Estes. The fast-paced show uses various filming and editing techniques to create tension and uncertainty around complicated storylines involving terrorism and deception.