After meeting with an ill childhood schoolmate, a woman named Miranda Green develops malignant tumors all over her body and dies. The Fringe team is called in to investigate, and Walter discovers a handprint on Miranda's arm. He hypothesizes that she somehow caught cancer by skin-to-skin contact.
Back at the lab, Walter attempts to retrieve a fingerprint from Miranda's arm. Olivia and Peter visit Miranda's workplace, and discover that the name of the man that she met with on the day she died is Neil Wilson.
After several nights of tossing and turning, Olivia confronts Walter and tells him that she wants to tell Peter the truth about his past. Walter begs her not to say anything, but Olivia is resolute in her decision.
Neil Wilson, now looking a little less sickly, goes to a grocery store to stock up on healthy foods.� While paying for his items, he becomes violently ill and runs out the door. Neil goes home and begins searching for another childhood schoolmate named Lloyd Becker.
When Becker turns up dead, Walter suggests that Neil may be infecting others with cancer in an effort to slow the progression of his own illness. Astrid finds three more similar cases, and Olivia discovers a commonality among them: all of the victims were Cortexiphan children.
Olivia goes to Massive Dynamic to see if Nina Sharp has a complete list of the Cortexiphan children's names, but she comes up empty handed. She tells Nina of her intention to tell Peter the truth, and Nina calls her bluff.
Meanwhile, Neil Wilson visits Nick Lane's aunt, and she unwittingly mentions that Nick (from the episode "Bad Dreams") was recently in contact with another Jacksonville schoolmate... Olivia.
