During season 2, Sydney continues to act as a double agent inside SD-6 and also performs direct missions for the CIA. Irina Derevko turns herself in to the CIA and provides valuable information to help bring down SD-6. Midway through the season, the CIA finally has enough information to bring down the entire Alliance organization and the assault on SD-6 headquarters, led by Sydney and Vaughn. The organization comes tumbling down, but Sloane gets away and is now working covertly with Julian Sark.