FlashForward - Season 1 Episode 19

Demetri and Agent Banks attempt to track down a killer as questions arise about the universe course-correcting itself, when people who thought they'd escaped their fates are found dead; Mark reluctantly agrees to help Simon find his sister, Annabelle, but discovers he's withholding the truth about her true circumstances; the FBI discovers the identity of Suspect Zero; and Nicole learns the whereabouts of Keiko - the woman in Bryce's flashforward - but struggles with whether to share this information, due to her growing feelings for him.