21. Search and Rescue

Complete story — includes the ending

The episode begins with a flashback in which Jack executes Irina 18 months prior. It was, however, not Irina who was killed and instead a double from the Project Helix. It is learned that Irina's death was an elaborate setup by Elena Derevko in which Jack was meant to execute the double to make everyone believe she was dead. The information on the double is confirmed through an encrypted file called the Blackwell File (retrieved in an earlier episode). With the knowledge that Irina was still alive, Jack, Sydney, and Nadia stage a search and rescue in Guatemala where Irina was being held. While all this is going on, a device known as the Mueller Device (Marshall calls it the Big Red Ball) is put into place over Sovogda, Russia, the entire population of which is rioting much like the frenzied bees from In Dreams.... The Rambaldi prophecy appears to be coming true and only Irina has the knowledge to foil Elena and Sloane's plot. The team makes a HALO jump into Sovogda in an attempt to shut down the Mueller Device. The Russian authorities have ordered an airstrike, but since rupturing the sphere would release a vast amount of toxins, time is running out.