Event Year: 2008

When the passengers on a commuter train all die instantly of massive power loss, the team realizes that a time traveler is responsible… and that it may be impossible to apprehend him. Meanwhile, Walter writes a letter to Peter explaining his origins.

A healthy woman dies of rapid-onset cancer in a matter of minutes, and the Fringe team is called in to investigate. The killer has connections to Jacksonville… and Olivia is a potential victim. Meanwhile, Olivia tries to come to terms with her knowledge of Peter's origins.

As the story shifts back to life “over there,” the absence of Colonel Broyles changes the dynamic of the Fringe Team as they investigate a bioterrorist armed with an insect that has a taste for human flesh. Meanwhile, alternate Olivia is reunited with her beau, and Walternate remains determined to save his world but discovers there are certain lines he will not cross.

When a scientist falls dead after ingesting a lethal cloud of blue powder and his bones disintegrate in his body, the CDC suspects a biological attack. As the Fringe Team investigates further, a subject from Walter's past with ties to Olivia reluctantly agrees to assist with the intense case.