Sydney Bristow, an agent who has been tricked to believe she is working for the U.S. government, is actually working for a criminal organization named the Alliance of Twelve. Upon learning this, Sydney becomes a double agent for the real CIA. | Action & Adventure, Drama | 5 Seasons | 105 Episodes | Series Premiere: Sep 30, 2001 | Last/Latest Episode: S05 E17 on May 22, 2006