|Season 3, Episode 20|
|Air date||April 22, 2011|
|Written by||David Wilcox|
|Directed by||Jeannot Szwarc|
Lysergic Acid Diethylamide
The Last Sam Weiss
|Cast | Transcript|
In the Alternate Universe, Secretary Bishop determines a method to refocus the damaging anomalies in his universe onto this one.
In the Alternate Universe, Walternate has been able to use the sample of Henry Dunham's blood to create a serum made up of half of Peter Bishop's DNA. He uses this serum to activate his doomsday machine at 6:02 AM. In the prime universe, this results in a series of unusual events, including the formation of a vortex that wipes out a long swath of land, including a herd of sheep and their herders that were on it. The Fringe Division learns that their version of the machine activated at 6:02 AM on its own, and Walter Bishop suspects the two machines are tied by quantum entanglement, with their version of the machine destroying their world to stabilize the parallel one. Unknown to the prime universe, Walternate's experiment has not affected the stability of their world.
In the prime universe, Nina Sharp helps to set up Massive Dynamic's resources to track these occurrences, preparing to deploy limited supplies of the Amber substance to contain them if needed. Nina advises Olivia to find Sam Weiss, a man that William Bell had trusted and instructed Nina to also listen to. However, Sam has disappeared and cannot be found. Walter and Peter, along with Massive Dynamic staff, debate on how to disable the machine, but Peter realizes that he himself is the only option. Walter comes to recognize that The Observer's efforts from earlier ("The Firefly") were to prepare him to lose Peter. After preparing himself, Peter goes to touch the machine but is sent flying by an electrical spark, wounding him and knocking him unconscious. At the hospital, Walter tries to find repentance from God for his actions, while Olivia arrives after hearing the news. She steps outside to observe the sunset when Sam Weiss runs up to her and demands to be taken to the machine to stop what is already happening.
In the parallel universe, Walternate's machine has been detected by the Fringe division and Fauxlivia and her team go to investigate. When Walternate tells them to stand down, Fauxlivia asks him about her recent mission to the prime universe and the part that she recovered. Walternate admits to her that the machine has been activated, having sacrificed his own son Peter to allow Fauxlivia's son to live. Fauxlivia becomes distressed at Walternate's actions, and later returns to Liberty Island to obtain the devices to allow her to cross to the prime universe, but is caught before she can use them. Walternate locks her away, seeing her as a traitor to his cause.
Broyles: The techs said they're ready when you are, Peter. Good luck.
Peter: If this works and I save both universes, I want you to consider me officially retired.
Broyles: I'll think about it.
Fauxlivia: What's going to happen to the people over there?
Walternate: My concern is for the people of our world.
Fauxlivia: But your son is over there.
Walternate: I'm aware. Peter chose to leave. He chose his allegiance. I chose to give up my son so that you could keep yours.
Olivia: And, uh, your father is walking around the house naked.
Peter: Oh, yeah, it's Tuesday. He always cooks naked on Tuesdays.
Olivia: Is that safe?
Peter: Uh-uh. It's not pretty, either. But you get used to it.
- In the lab, Walter, Peter, and Astrid are conversing together while Olivia is in the background talking on the phone. She is seen hanging up the phone and walking back to the group twice.
- Rocky Mountain Way by Joe Walsh