The copycat archer has killed a bunch of UNIDAC scientists. Oliver, Diggle, and Felicity are able to determine that there is some link between UNIDAC and Merlyn Global. Quentin has made a similar, but not clear connection.
Laurel visits Oliver at the club. She tells Oliver she still has feelings for him, and he’s changed since he came back. Oliver tells her he hasn’t and he doesn’t want to get in the way of her and Tommy.
Walter arrives home from the hospital, but seems a bit cold towards Moira. Oliver tries to confront Moira about The Undertaking, but she has just seen the news of the UNIDAC murders, and knows Malcolm was involved. She hurries out of the house before Oliver can talk to her.
Oliver is finally able to talk to Moira, and asks her who took Walter. She won’t tell him, and as he is trying to get her to be honest with him, they are both hit with poison/tranquilizer darts. They awaken in a dark room, tied up to chairs.
The (what I thought) copycat archer is interrogating them, but it is actually Diggle pretending to be The Hood. He gets Moira to give up that Malcolm is using the Markoff Device to create an earthquake in The Glades to wipe out the population and rebuild. Robert Queen got involved, but when it turned bad he could not get out. Moira got dragged into the situation and is just trying to save her family. The Hood then cuts them free.
Felicity is able to find out that UNIDAC has a product specializing in seismic infringement, a manmade earthquake. She also finds that the copycat archer works for Merlyn. They need to find the Markoff Device, and Felicity is trying to hack into Merlyn Global’s computer system.
Malcolm visits Walter to see how is doing. As Moira is walking Malcolm out, she asks why he had the copycat archer kill all of the scientists. Malcolm explains that the police will be worrying about that case, and not The Undertaking.
Felicity is unable to hack into the computer system, and offhandedly mentions that if she could hook up her tablet to the mainframe, she could get whatever they needed. Oliver decides that they need to get into Merlyn Global and do just that.
Oliver sets up a meeting with Tommy, Felicity pretends to be delivering lunch to a security guard, and Diggle is the “new” security guard. The lunch that Felicity brings has some kind of drug in it, which incapacitates the other security guard. Felicity and Oliver take the elevator up to the 24th floor. The computer system is on the 25th.
Oliver and Felicity climb on top of the elevator, and make their way to the 25th floor. Oliver heads off to his meeting with Tommy, and Felicity goes into the computer room and starts downloading from the mainframe. Diggle is watching them, and notices some security guards making their rounds early.
Oliver has a very short meeting with Tommy, telling him that he can’t be with Laurel, so Tommy should. Tommy doesn’t want to be the consolation prize. Oliver tells Tommy that he couldn’t handle being with Laurel and it’s his own fault, not Oliver’s.
Oliver tries to make it over to save Felicity, but runs into Malcolm. Oliver and Malcolm head down to the lobby together, and Felicity finishes the download. She heads out and runs right into a security guard. She is trying to figure out how to get away, when Diggle comes up grabs her, saying she is one of Tommy’s ex girlfriends that is obsessed with him.
Oliver is trying to go back upstairs when she runs into Thea in the lobby. Thea tells Oliver that Roy is trying to find The Hood. Oliver grabs Roy and tells him they need to stay away from this so that Thea doesn’t get hurt. Felicity is shown leaving the building as Oliver is talking to Roy and Thea.
Back at Roy’s house, Roy wants to trail a vertigo dealer to see if The Hood shows up. Thea is getting sick of this, and Roy says he wants to be like the vigilante so he doesn’t lose anyone else. Thea says if he doesn’t stop, he’ll lose her. He tells her better now than later, and she leaves.
Walter gives Moira divorce papers. He thinks she had something to do with is kidnapping, since he was kidnapped the day he confronted her about the notebook. Moira tells him that she saved his life, but he feels that she has destroyed it. He’s surprised he even survived, since he didn’t have that drive to stay alive to see his family again.
Quentin had someone in the department try and hack into Merlyn Global’s computer system, but he wasn’t able to get in. But, he did find that someone else was trying to hack in as well. It was Felicity.
While Felicity is trying to find the location of the Markoff Device, Oliver is rethinking his redemption plan. He thought he had to find all of the names in the book. But he realizes now that he was just treating the symptoms while the disease festered. If he can stop the destruction of The Glades, the disease will be killed. Diggle asks him if that means he will take off the hood after.
Oliver goes to see Laurel. He tells her that she is more important to him than anyone. They kiss, and end up in bed together. Before they make it to the bed, Tommy is outside Laurel’s building (unclear if he was coming to see her or if he was just walking by) and sees them through her window.
Oliver is woken up by a call from Diggle. Felicity has been able to track the location of the device to a warehouse owned by Merlyn Global. Diggle will go to the device, and Oliver will go to Malcolm. When Diggle gets to the warehouse, the device is gone.
Malcolm tells The Hood that the tracker they put in his computer tipped him off that he should move the device. He tells The Hood that he can’t stop what is about to happen, and these people need to be erased from the map. They fight, and Malcolm eventually gets the upper hand, knocking The Hood out. Malcolm takes his hood off, revealing him to be Oliver.
In the flashback portion of the episode, Fyers is going to blow up a plane, straining the Chinese economic system. He will use Yao Fei as a scapegoat for the crime. When Fei says he won’t do it, Fyers shoots Slade in the leg and Shado in the arm, saying that Fei needs to stay alive, but they do not. Fei agrees to do it.
Fei sneaks a knife to Oliver, and Fei records a video for Fyers taking responsibility for the upcoming attack. After he is done making the video, Fyers shoots him dead. Oliver is still cutting the ties on his hands with the knife.