At the British History Museum in Lakefield, IL, Pete and Myka go in after hours to collect what Pete believes is an elephant walking stick that causes earthquakes. Myka isn't convinced and notes that there's no evidence that the stick, locked in the case, has been used. Pete starts messing with the museum exhibits, including a hearing aid and a telegraph. When a security guard comes in, they hide and watch as the man takes the stick out of the case. The agents figure he takes it out of the case when he's not using it. They close in but the security guard, Malone, uses the stick to generate an earthquake to cover his escape. Pete and Myka split up and Pete runs outside. He finds Mrs. Frederic waiting for him. She tells him to drop the case and tell his teammates nothing about meeting her. Mrs. Frederic drives off and Pete lies to Myka when she comes out, saying that Malone got away from him.
The next day, fellow Secret Service agent Kate Logan from the Chicago field office arrives and confirms Pete and Myka's credentials. She and Pete go back and it's clear they have some history. She's curious about his transfer to South Dakota, and tells him it doesn't matter whether Pete calls her late or not. Once they're alone, Myka wants to know how Pete lost Malone, but he insists he got unlucky. Artie calls and tells them to come back to the warehouse. When they arrive, they find one of the Regents Benedict Valda, waiting for them. Artie complains but Valda overrides him and points out the agents are compromising their confidentiality. He tells them that the Regents will be taking a more direct hand. When Claudia object, Valda warns her that her position is under particular scrutiny, and hands her a flash drive. Artie takes it and orders Pete and Myka back to Illinois to find the stick. Myka blames Pete and starts to go, but he says he has a thing and stays.
Later, Pete meets with Mrs. Frederic near an abandoned plant. She informs him that there's a breach and someone among the Regents is using artifacts for criminal gain. When Pete wonders why Valda was there, Mrs. Frederic suggests that any change in plans would have alerted the mole. She figures Pete is the last person anyone would suspect of keeping secrets. Mrs. Frederic tells him to keep an eye on Malone, and contact her when his supplier makes contact. She tells Pete to break a window in the plant when he has something to report.
At the warehouse, Claudia hacks the flash drive information and decodes the file.
Pete and Myka check out Malone's apartment. She discovers the power is out and flips the switch repeatedly. Pete looks out on the streets and spots Malone with someone. He offers to go check the trash on his own and then goes down and approaches Malone and his supplier. It's Valda, collecting his payoff. Pete draws his Tesla and closes in, but Myka calls for him, giving him away. Valda runs off and Pete stuns Malone, and then goes back to get Myka. However, when they return, they discover that Malone has vanished.
Pete meets with Mrs. Frederic at the plant. As she taps her finger nervously, she warns that telling Artie and Myka will put them in danger because the Regents have full authority to kill anyone. Mrs. Frederic wants Pete to get Malone and the walking stick so they have the evidence to take down Valda. She advises patience, but Pete warns that he isn't good at patience.
At the B&B, Pete finds Myka going over Malone's belongings from his apartment. He checks the last number dialed on Malone's phone and he discovers Malone called a motel in Lakefield. As Myka wonders why Malone was there, Pete takes the battery out of his phone and lies about what came up on the redial. He leaves and Myka notices Pete in one of the surveillance photos. She realizes that he's up to something.
Claudia talks to Artie about her dossier, and admits that Todd dumped her. She then notes that the file has means of disposing of her. Artie says that there's a file for all of them, and insists that no one is going to dispose of her because she's a valued member of the team. Myka comes in and suggests that Pete is drinking again. They stage an intervention and Pete denies that he's drinking. He tells them they're wrong and walks out.
Pete goes back to the plant and breaks a window, and Valda calls him on his cell phone. He directs Pete to an envelope with photos of Pete and Mrs. Frederic together, and warns that if Pete doesn't deliver Malone, he'll have his man kill Mrs. Frederick and the entire team. Pete warns that he doesn't know who he's messing with, goes back to his room, and packs guns and explosives to deal with Valda. He leaves a note for the others. Myka finds the note and they realize that Pete has taken himself off the grid.
Pete calls Kate and leaves a message for her to find an address on Valda. He then goes to the motel and captures Malone, handcuffs him to the radiator, and demands to know where Valda can be found. Malone claims to have no idea who Valda is, but admits he took the stick. He directs Pete to the hidden stick, and Pete takes it and leaves.
In Chicago, Pete goes to an outdoor café and meets with Kate, as a waitress stares at him, surprised. Kate says that people have been after her since she started looking for Valda. She demands answers and Pete tries to explain that he's protecting the planet without saying anything specific. He suggests that Kate check nearby gas stations to see if Valda stopped for gas. Kate agrees to help and then kisses him. They end up in bed but Myka bursts in. She orders Kate out and asks for answers, and warns that Mrs. Frederic is missing and Valda is in charge. Pete knocks her down with the walking stick and runs out to the street, and Kate pulls up. As Myka arrives, Pete spots a sniper on the roof. Before he can do anything, the sniper kills Kate. Desperate, Pete runs off before Myka can stop her.
Myka goes to the Secret Service field office and talks to… Kate, alive and well. She explains that Pete is suffering from paranoid delusions, but can't explain is causing the behavior. Myka has surveillance footage which shows Pete at the outdoor café... kissing empty air. Kate gives Myka the message Pete left her about Valda. Myka then goes back to the museum and contacts Artie, and confirms that Pete touched things there. She shows Artie everything that Pete touched, including the telegraph. Artie recognizes it as being from Telegraph Island in the 1860s, and confirms that it caused delusions in the soldiers posted there.
Pete tracks Valda to Cleveland and leaves a note on his windshield. Myka calls him and she tries to get through to him. He insists he's going to protect her but she tells him to brace himself and puts the telegraph in a neutralization cylinder. Peter hallucinates Valda coming on the line and warning him that he's going to have to eliminate his teammates. Valda and his bodyguards leave and Pete follows them, and Myka calls Artie to warn that destroying the telegraph had no effect. Artie has an idea.
Pete meets Valda at the recycling yard and stuns his bodyguards, then ties up Valda and tells him to drop the pretense. Valda has no idea what he's talking about but realizes the telegraph is affecting Pete. Pete remembers all the times he heard the rhythm on the telegraph during his hallucinations but figures Valda is trying to trick him. Myka and Artie arrive and Pete takes cover. He tries to explain that someone is messing with his head, and Myka promises they'll help him. However, Pete starts hearing Valda threaten to use his hidden snipers. Pete slams the walking stick down, triggering another earthquake, and demands to know where Mrs. Frederic can be found. Artie turns on a tape of Oye Como Va
to break Pete out of the spell, but it doesn't work. "Valda" boasts that Myka is going to kill Pete for him, and then he'll kill Myka and Artie. In the hallucination, he breaks free and kills Myka and Artie. He then shoots at Pete, hits the propane tanks behind him, and sets off a huge explosion.
There's a flare of light as Artie focuses a Tesla through a discarded windshield. The combined visual and aural stimulation breaks the spell and Pete returns to normal.
Later at the warehouse, Pete is writing his report when Mrs. Frederic appears. She explains that Valda understands the circumstances, and the telegraph tapped into his subliminal anxieties. Once he makes sure that she's real, Mrs. Frederic tells him to take some time off and disappears.
At the B&B, Claudia gives Artie her own preference for how to take her out. He tells her that he doesn't know David Bowie. Pete and Myka come in and find there's an envelope from Kate. Myka figures she has some feelings for Kate but Pete denies it. Inside the envelope is a get-well note and a copy of the surveillance footage on a memory chip. Pete plays it back despite Myka's warnings that he'll be embarrassed, but he's satisfied that he's still got the moves even by himself.