Event Year: 2008

The team is called in to investigate why a man jumps out a window because he thinks he's being attacked by butterflies. Olivia gets some breaks in solving the case from her former partner and that she is so desperate to rid herself of him that she demands to go back into the tank. Meanwhile, some former friends and current foes of Peter find out that he's back in Boston.

Walter thinks the abduction of a young music prodigy is linked back to his old bunkmate at St. Claire's Hospital. When he kidnaps the child he sees a sequence of flashing lights. Olivia wants Walter to return to the mental institution much to Peter's outcry, but Walter's determination to help ends up having chilling ramifications.

When a strange parasite attaches itself to the internal organs of a dying FBI agent, Olivia suspects a connection to the Pattern; Peter and Walter tap into a dead man's brain waves.

Human beings are reduced to ash statues and Broyles realizes that the same person responsible murdered five other persons four years ago… a case that he never solved.