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.
Season: 2
Olivia. In the Lab. With the Revolver.
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.
Humpty Dumpty
Cuddy struggles with a case of guilt when her handyman is injured while at her place, and House and his team have to work fast to save the young man's pursuit of the American Dream.
Autopsy
A girl's unimaginable bravery toward her terminal illness makes House suspicious as he puts a life-or-death decision about her case in her young hands.