After making a shocking discovery of a severed human hand in the desert that belonged to Lazarey, the Russian diplomat she murdered while working as a brainwashed assassin for the Covenant, and who may in fact be alive, Sydney agrees to submit to an experimental procedure conducted by an eccentric doctor, named Dr. Brezzel, designed to retrieve her lost memories. But while Jack and Vaughn look on, Sydney's mind proves surprisingly resistant to letting her remember her missing time... and the process of recovering it could end up killing her. Meanwhile, Lauren makes a great sacrifice of allowing herself to get tortured and beaten up in order to make her alibi believable to Lindsey after helping breaking Sydney out of NSC custody. Also Sloane finds himself boxed in by an unlikely enemy, that of Mr. Lindsey, who wants to see Sydney Bristow eliminated permanently.

During a mission to Austria, Sydney must protect the life of an American civilian, whom she unintentionally put in danger after she acquires information about a new mini-helicopter to be used as a weapon. Meanwhile, Jack travels to Madagascar to visit with an old friend, the arms dealer Sasha Korjev whom is the mastermind behind the assassin helicopter. Back in Los Angeles, Vaughn uncovers more disturbing secrets about his father of finding a diary with notes written years after his alleged "murder," which straightens his quest to know if his father is really alive.