Dylan watches the detectives talking about the search for Gwendolyn and makes snarky comments about their competence. He is impatient as they go through the timeline. Stroh's mother apparently abandoned him in some boarding school which bothers Rusty.
Stroh's stepsister comes to talk to the detectives and says Stroh was always odd. She hasn't thought about him in years. Stroh was always a psychopath. Rusty is bothered by Stroh's mother having abandoned him by sending him to boarding school.
Dylan continues watching. Someone gives him a 30 second view of Gwendolyn's new documents. He is excited that he found her first. Meanwhile, Andy comes to get Rusty but says he will go home when Stroh is dead.
Mason has some info about Gwendolyn but doesn't think he has enough to get a warrant to get her location. Julio and Skyes suggest he point out that her life is in danger.
Gus comes to the station to bring Rusty food and recognizes Stroh. He tells the team about seeing him at the restaurant the night Sharon died. He calls his manager and Provenza gets on the phone to try to find out if Stroh used a credit card.
Dylan visits some girl named Ella and freaks her out by saying he's gonna get a lot of money from some old lady. She throws him out but wants to be paid first.
Someone takes a photo of Rusty as he is leaving.
The team discovers that someone has edited the security footage from Gus' restaurant to get rid of Stroh on the tape. Mason won't approve funds to protect Gus because he thinks there's no proof Gus actually saw Stroh.
The team visits Abigail aka Gwendolyn. She has dementia and tells the detectives only that she knew they'd find Mary Wellington someday.
Chief Mason does not want to pay for a security detail for Gwendolyn. Provenza suggests that Gus and Rusty stay together to save money.
Paige suggests Dr. Joe talk to Gwen to get through to her about Mary, while Dylan insists to himself he's way ahead
Gwen tells Dr. Joe that Philip was always a problem but she never guessed he would do anything to Mary Wellington. There is a creepy flashback of Philip telling Gwen that Mary called him names and hit him so he had to defend himself. Mary was raped and murdered. She decided to help hide the body in a house her husband was pouring the foundation for so that Philip wouldn't get in trouble. Only Jim guessed anything was wrong. Philip didn't look guilty. He got sent to boarding school after he set the house on fire. She and her husband divorced when he found out she was visiting Philip. She gave Philip money to get out of the country before changing her name and disappearing forever.
The team argues about what to do about Gwen. A guy named Hunt Sanford shows up and says they have been bothering his mother and making her upset. Dylan is mad that the cops found Hunt before he did and rants that it isn't fair.
Rusty is upset that Stroh has a similar background to him. Andy tells him he is not a serial killer. Rusty says Sharon was right that he has to identify with Stroh to catch him. Andy tells him that he and Gus must stay in the squad room until they get an escort and that they must not split up.
Meanwhile, Dylan freaks out when he overhears Hunt say he has private security cameras installed in Gwen's bedroom and Buzz says they are not hackable. However, Dylan is able to hack into the team's monitor and corrupt the file just as they are about to see his face.