Sydney and Tom travel to Marseilles, France when they discover that Renée has stolen the cryo container which contains the cryogenically frozen body of her supposedly dead father. But they soon find themselves under siege in Renée's warehouse hideout by a group of mercenaries who want to reclaim Renée's father when he awakes up from his cryo-induced sleep... so it appears. Meanwhile, Rachel and Dixon travel to San Francisco to assist Marshall in the break-in of a vault facility to copy files to learn more about Renee's father. Elsewhere, Sloane takes matters into his own hands to get himself back into APO and continue his quest to find a cure for Nadia by influencing/blackmailing a influential senator to let him have full access to the CIA's accessories.

When Kelly Peyton steals some software from a CIA warehouse concerning the late Michael Vaughn, Sydney is soon abducted by Prophet Five agents where she is subjected to a hypnotic state making her flash back to her happier times with Vaughn in order to learn where a supposedly powerful device, called The Horizon, is located. Meanwhile, Jack must team up with Renée to locate Sydney when they captured and torture Aldo Desantis, while the mastermind behind Prophet Five is finally revealed... and why the person has a strong interest in Sydney's unborn daughter.