 After a tactical group infiltrates the DSR and steals all the Rambaldi artifacts, CIA director Hayden Chase discovers that the alarms at the DSR were disabled from Nadia s computer, allowing the raid to happen. Mrs. Chase shows up at the apartment to question her. Soon Sloane and Jack arrive and suspect that Sophia, who had access to the computer while she was living with Sydney and Nadia, is in fact Elena Derevko whom has doubled to impersonate Sophia using the Helix technique. They follow her trail to a dead Rambaldi follower, a stunning betrayal, and a presumed dead family member when in a surprising twist, Sydney and Naida learn that Irina Derevko is in fact alive and that it was another Helix double of Irina that Jack assassinated in Moscow two years earlier.