Peter flirts with a young waitress in a diner. She promises to make him a CD and bring it to his hotel later that evening. On the way to her car she is abducted, violently murdered, and a piece of her brain is removed.
The next morning, Peter goes to the diner and is stopped by the police. Krista, the waitress, is now missing. The police take Peter into custody, and on the way to the station they get a call. Krista's body has been discovered with a piece of her skull cut out. She is missing a piece of her temporal lobe.
Peter knows about the temporal lobe, because of a past case he was not able to solve involving Thomas Newton. Newton removes a piece of someone’s brain to read their past thoughts.
At his hotel, Peter receives another strange call. He then gets a call from Sheriff Mathis, Ferguson, her partner, is missing.
Back in Massachusetts, Walter has a complete meltdown in a supermarket. He is extremely upset about Peter's disappearance. Astrid takes him home and sees that Walter is not taking care of himself; he doesn’t even have food to eat.
Peter and Mathis get a call, a young unknown female victim, with her skull missing, is discovered.
Peter then comes up with a plan to find Newton. The tissue in a victim's body produces a spike in adrenaline right before his/her death. Peter discovers by finding the time difference between the two corpses, he can find the kill zone on a map.
The kill zone leads them to an old dairy farm. Mathis questions a man, and believes he is who he is supposed to be. She goes to call for backup and the man attacks Peter. Peter fights the man and they find Ferguson alive.
Walter creates a machine to help locate Peter. He intentionally puts in the wrong numbers, because he is scared Peter won't forgive him. Walter is also scared of being sent back to St. Claire’s.
Olivia goes to the lab and tells Walter she has located Peter in WA.
Back at his hotel, Peter gets a visit from Newton and the man that has been trying to find him... his real father!