Myka and Pete confront Artie and asks what Adrian wants, but Artie refuses to talk about it. He tells the agents that they have a ping, Leonard Bukowski of Dalton, West Virginia, who is displaying signs of rust. Artie sends them on his way and Myka warns him that one day they'll actually have to tell them things. Once they leave, Claudia and Steve come in and demand to know about Adrian, but Artie tells them to focus on the metronome. Musician Robert Schumann owned the metronome in the 1830s and tried to kill himself, but his fiancée kept him alive using it. In 1839 Schumann got free of it and left an entry saying that one must make a pure start from where one comes. They figure that it relates to Steve returning to his home in New Jersey.
Once they leave, Artie sits down to study the data on Adrian, and Mrs. Frederic, Leena, and Helena come in. They demand answers, aware that Artie has altered time. He insists that he had no choice because the warehouse was gone and Mrs. Frederick and Helena were killed. Artie explains that Pandora's Box was destroyed and he had no choice, and Mrs. Frederick agrees with his decision. She asks what the repercussions are and Artie tells her about Adrian's prediction of a great evil.
In Dalton, Pete and Myka talk to Lenny, who explains that he works at the local steel mill with most of the men in town. He hasn't received any recent artifacts and the only person who hates him is mill owner Hank Siskel, who has been withholding checks and laying off workers. Lenny starts to have another rust attack and the agents leave.
Steve and Claudia arrive at Steve's home and he explains that he and his mother Emma had a fight. Claudia insists that they go in and Emma greets them at the door. Steve introduces Claudia and Emma Jenks cheerfully invites them both in.
At the steel mill, the workers are protesting and refusing to leave. Siskel arrives and tries to force his way in and the agents jump in to try and prevent a riot. Once the owner goes in, the agents explains that they're checking out what may have caused Lenny's illness. The union rep, Sam Garity, explains that there have been a series of recent accidents and blames Siskel. Lenny's doctor calls to say they had to remove parts of his patient's lung to save him, and another worker on the picket line, Tim Watts, starts coughing up rust.
The agents take the new victim to the hospital and call Artie, but admits that they don't have any proof. They figure that Siskel wouldn't call attention to himself, but Myka confirms that Sam had fights with both Lenny and Tim. Artie tells them that Siskel changed his name from Hank Blaloc in 2001 but is clearly distracted. Mrs. Frederic interrupts and tells them to handle it, and then demands answers from Artie. He admits that the evil may be Claudia because he's been having visions of her stabbing him with a dagger. Mrs. Frederic says that she would know if Claudia was evil and suggests that Adrian is the evil.
At the Jinks home, Emma makes tea and admits that Claudia reminds her of her daughter. Steve interrupts her and she drops the subject. She asks if Steve is with the ATF and he says that he is but that she can't come to see him. Emma finally says that it's been two years and she loves him, and asks when they're going to talk about it. Steve says that they're not going to talk about it, and once he's done they'll be leaving. His mother tells him that she doesn't want him to go and walks out.
Artie tells the others that Adrian wants them to use the astrolabe but he won't, and tells them that it's safe. He wonders why he's having the visions about Claudia and Mrs. Frederic suggests that Adrian has implanted a subconscious thought. She says that she'll talk to the Regents and see if they can reach out to the Brotherhood through other channels. As Leena and Mrs. Frederic go, Artie tells Helena that he didn't want her to involve the others. She says that she's already lost two agents to time travel and doesn't want to lose any more, but Artie wonders if they won't all regret it.
Myka goes to the steel mill and asks for Siskel. When he comes out, Pete sneaks into his office and looks around for artifacts. Meanwhile, Myka brings up the rumor that Siskel made Tim and Bukowski sick, and he insists that he's doing everything he can to keep the mill open. She accuses Siskel of hiding his accident record to protect his insurance rating and notices his belt buckle. Pete, contacting her over the earbud, says that he's turned up nothing and that they got a call from the hospital. There's a third victim but she's never been to the mill, meaning Siskel is in the clear.
Steve and Claudia go to the living room and take out the metronome. Claudia is still reluctant to endanger her friend but has him put her hand on him and focus. Nothing happens and Steve stops the metronome... and they both start choking. Emma hears them and runs in as Claudia starts the metronome again. Steve angrily says that he came there for nothing and walks out, and Emma asks Claudia to tell him what is going on.
At the hospital, Myka talks to the new victim, Karen Miller. She confirms that she's never met Siskel or been to the steel mill. The doctors tell Pete that Bukowski and Tim are going downhill. They realize that she exercises at the same gym, Tully's, that Tim and Lenny work out at. The agents go to the gym and talk to Tully, who confirms that Siskel never comes there. Sam comes in with his friends and the agents say that Siskel can't be involved. The workers don't believe it and they insist the agents should be on their side. Once Sam and the others walk away, the agents wonder if Sam is responsible and Pete suggests they do a little one-on-one interrogation.
Pete gets into the ring and starts sparring with the workers. As they fight, he asks about Sam and his doing anything unusual. Meanwhile, Myka checks in with Artie to see what he's found in the database. Artie also confirms that Siskel owned a restaurant in Oakland in 1996 and was arrested for abusing his busboys. Meanwhile, Sam gets word that Pete is asking questions about him and confronts him in the ring. Pete points out that if the town hates Siskel then it works out for Sam, and Sam jumps him. Myka signs off and goes to stop the fight, but another worker, Cody Bell, enters the ring and takes on Pete. They both served in the Marines but when Pete explains that Sam has a motive, Cody knocks him to the mat.
Claudia hesitantly explains that Steve is connected to the metronome, and Emma figures that he came there to talk about what happened. She admits that Claudia looks just like her daughter Olivia, Steve's sister. Emma explains that the man who killed Olivia was considered for the death penalty but she fought against it. Steve felt she had betrayed Olivia and then left rather than try to resolve their differences. As Claudia looks at the family photo, Emma reads Schumann's entry about making a pure start and says it reminds her of a poem she read when her children were born.
Myka wakes up Pete as Tully introduces the big fight between Todd Murray and newcomer Cody. She tells Pete that she saw a shadow on his arm and heard a yell just before Cody hit her. Pete still figures that it's Sam and confronts the union rep, warning him that people are dying. As Cody fights, Sam explains that the Marine's father Charlie was hurt in one of the mill accidents. As Sam starts coughing, he confirms that Cody went out with Karen before realizing that he's coughing up rust. Pete takes Sam out while Myka takes a photo of Cody as he delivers the knockout punch and the crowd cheers on their town hero. When Pete returns, Myka shows him the photo which reveals a ghostlike metal structure around Cody's left arm.
Claudia goes to Olivia's room where Steve is meditating and he admits that the whole situation is making him insane. She suggests that the poem refers to Steve being born and the love between a mother and son, and Steve says that it's all over. He wonders how she can keep Olivia's room intact but fight for her murderer's life. Emma comes in and insists that they're separate things and that the hate and anger isn't good for him. When he wonders how she can turn her feelings on and off, Emma says that she has to forgive Olivia's killer over and over. Steve admits that he can't and Emma explains that while he thinks about the killer every day, she thinks about Olivia. As Emma leaves, Steve admits to Claudia that he wants to let it go but he doesn't know how. Claudia suggests that he think of Olivia and goes.
At the hospital, Pete and Myka talk to Cody's father Charlie, who says he's never been to Tully's Gym. He suggests that Cody's strength comes from his anger over the accident and explains that Cody saved his life when the gantry he was on fell. Cody wasn't able to hold him and until he found a sudden burst of strength, lifting Charlie with one arm. Myka suggests that Cody might be suggesting something to boost his strength but Charlie insists that his son isn't juicing. He shows them a newspaper article about how Cody saved two of his squad members from an explosion at the Baghdad National Museum in 2005.
The agents check with Artie, who confirms that the south wing houses Peloponnesian artifacts tied to their fight against the Persians. The artifacts are rumored to give the user the strength of the 300. Myka realizes that Cody was hit with shrapnel from the artifact during the explosion and it is embedded in his chest on the left side, the same arm that he touched all of the victims with. Pete points out that Cody touched him with his left arm, and Artie figures that Cody has to be in an emotionally-heightened state. He didn't affect Charlie when he saved him because that was the incident that activated the artifact. As they talk, they're unaware that Cody is listening into them until a nurse calls to him. He angrily asks the agents when they were going to tell him he was making people sick, shoves Pete aside, and runs out before they can stop him.
As Emma looks at the metronome, Steve comes down and apologizes, explaining that if he let go of his anger he felt he might let go of Olivia as well. They hug and Claudia touches the metronome. It glows and Emma starts choking. Steve throws it against the fireplace and it explodes in a blast of light. Emma recovers and Steve realizes that he's still alive despite the fact that the artifact is destroyed. Claudia suggests that Steve committed an act of pure love by sacrificing his life to save her.
At the mill, Cody uses his newfound ability on Siskel's guards and then grabs the owner. He accuses Siskel of setting up the accident that injured Charlie and prepares to crush him with his new strength. Pete arrives and shoves the owner away, taking the punch. The agent tries to get through to Cody as Myka takes down Siskel. Cody tries to push back Pete and hits him again, causing him to rust. Pete grabs him again and insists that he won't let Cody give up on being a hero, but Cody keeps hitting him.
Myka tells Siskel that she knows who he is and threatens to reveal him until he admits that the gantry was rigged for the insurance money. Siskel says that they weren't supposed to fix it and nobody was supposed to hurt, and Myka tells him that he's going to make things right.
Pete grabs Cody and dares him to hit him again, asking if he's a killer. Cody says that he isn't and Pete collapses. Myka runs up and tells Cody that they have to neutralize the shrapnel in his chest. Cody explains that it's up against his heart and removing it will kill him. As Pete chokes on the rust in his lung, Myka tells Cody to bring him a first aid kit. She then fills a syringe with the neutralizer fluid and prepares to inject it into Cody's chest. When she hesitates, worried that it won't work, Cody tells her to save Pete and the others no matter what it takes. She injects it into his chest and the fluid neutralizes the artifact shrapnel while keeping Cody alive. Pete recovers and they realizes that Myka's plan worked.
As the EMTs arrive and treat Pete, Cody thanks the agents for their help. He tells them that Siskel called Sam and offered to negotiate in return for a truce. Pete and Cody give each other a Marine salute and tell each other to take care of themselves. Once Cody leaves, Myka tells her partner that she just did a little hands-on interrogation that she learned from her partner to get Siskel to cave.
At the warehouse, Mrs. Frederic and Helena follow Leena's directions and secretly remove the astrolabe from the Dark Vault hiding place where Artie put it. Mrs. Frederic gives it to Helena and tells her to make it disappear and go off the grid while she deals with the Brotherhood. As Helena goes, Mrs. Frederic tells her not to trust anyone.