Helena wakes up next to a sleeping Oliver. As she slips away, he watches her go.
Helena drives to where the Triads are scouting out an alleyway. China White emerges from the shadows with Zhishan, the Triad leader and Helena prepares to shoot, but Oliver comes down from the roof, knocks Helena aside, and returns fire as the Triads shoot at them. They drive past, still firing, and Helena tells Oliver to take his hands off of her. She explains that when she killed Zhishan, the Triad will assume that her father is responsible and destroy the organization that she weakened. Oliver insists that it's not justice and offers to show her what he means.
Oliver takes Helena to Carly's restaurant and Carly wonders where her brother is. Once she leaves, Helena tells Oliver that she's not looking for anything permanent. He insists that he only kills people when he has to and warns her that she may get someone hurt, like herself or Moira. Helena explains that she's stripping everything from her father but Oliver offers her a way to take down his organization without putting innocent people at risk. She refuses and walks away.
The next day, Oliver is exercising at the hideout and Diggle wants to know what happened since Salvati has turned up dead. Oliver finally tells Diggle that he had to reveal who he was to save Helena, and explains about Helena was going to turn over evidence against her father. Diggle is impressed but warns that if she sets off a mob war then innocents will be killed in the struggle. Oliver wants to help her but Diggle doesn't believe it and warns that it'll end badly. Despite that, Oliver says that he has to try.
Walter is leaving for work and Moira points out that she isn't talking to him. She admits that his finding out that she had Robert's yacht salvaged could come as a surprise, and assures him that she's still the woman he fell in love with and married. Walter kisses her and says that they need to be honest with each other, and Moira agrees. Thea interrupts them to ask Walter for a ride to school.
Helena comes downstairs and finds Frank talking to Salvati's wife, Dina. They offer their condolences and when Dina leaves, Frank vows to make the person responsible pay. The doorbell rings and Frank finds Oliver at his doorstep. He apologizes for dropping the ball on the construction deal, but Oliver says that he's there to see Helena. Frank realizes that they're involved and quickly leaves the room. Once they're alone, Helena says that she isn't interested in talking and Oliver invites her along, saying she doesn't have to talk.
Oliver takes Helena to the cemetery and Sara Lance's tombstone. He explains that things were serious between him and a woman and he didn't handle it well, so he started sleeping with the woman's sister. Sara died on the yacht. As Helena takes his hand, Oliver admits that he was an awful person before the island and he hurt the people he loved. He tells her that she's on an island as well and Helena admits that she wants to open up to him. However, after Michael she doesn't want to be hurt again. Oliver promises that he will never hurt her.
Helena soon begins practicing archery with Oliver at his hideout. She doesn't do well but Oliver insists that she has to learn patience and discipline. Oliver demonstrates his own abilities and then explains about the list that Robert left him. Helena recognizes one of the names, Anthony Venza, as a drug dealer who works with her father selling illegal prescription pills. Diggle comes in and Oliver tries to introduce him, but Diggle isn't interested. Helena leaves them alone and Diggle warns Oliver that he doesn't trust the girl. He wants to know if Oliver is sleeping with Helena and figures Oliver wants to change her so he can prove he handle his own issues. Oliver ignores him and Diggle tells him that he's done... for the moment.
Tommy comes by to see Laurel and says that he has a date at a high-class restaurant. She points out that he's out of money after his father cut him off, and suggests that he ask Oliver for a job at his club since Tommy is experienced with partying. Tommy agrees and says that he'll talk to him later.
Felicity visits Walter and tells him that someone else was monitoring Moira's transfer of funds to finance the shipping of the yacht. She managed to find a symbol and shows it to him, and Walter tells her that she's to discontinue probing into Moira's affairs or he'll suspend her. Felicity makes a hasty exit and Walter examines the symbol.
Helena comes back to the hideout and Oliver tells her that they're going after Venza but on his terms. He has a weapon for her: a crossbow. He also has a costume for her, in purple.
Venza is at his warehouse showing off his product to prospective dealers when the lights go out. The dealer sends his men to investigate and after a moment a gun comes sliding across the ground. Arrow and Helena, wearing her new costume, step out of the shadows and tell Venza that he's failed the city. They tear into Venza's men, take them down, and cut off the dealer before he can escape.
The police soon arrive and Oliver and Helena watch from the shadows. Oliver points out that no one had to die and asks what she thinks, and Helena admits that it feels good as she kisses him.
The next morning, Helena finds her father drinking and listening to the news about Venza's arrest. He admits that he's had another business setback and figures that she's dressing up for Oliver. Frank is glad to see her happy again and is interrupted when his phone rings. As he deals with his people, Helena walks out.
Moira is preparing for an art board meeting and tells Walter she'll be back later. Once she's gone, Walter goes through her dressers to find anything. He finally discovers a wooden box with a symbol on it in the grandfather clock. Opening it, Walter finds a small journal filled with blank pages.
Tommy and Laurel go to the restaurant and wait. Tommy finally approaches the hostess and tries to get to the head of the line, but she isn't interested unless he can pay. Oliver and Helena come in and Oliver introduces them to Helena. They get a table immediately and Helena invites them to join her. Tommy and Oliver aren't interested but Laurel leaps at the opportunity. They talk about some of Tommy's pranks and the fact that his father didn't appreciate them. Oliver explains that the three of them have known each other for what seems like forever, and Laurel realizes that Tommy didn't ask Oliver for a job. Oliver chuckles at the thought and Laurel points out that he's always wanted to get into business with his friend. When Oliver mentions that they used to be lovers, Helena realizes that Laurel is Sara's sister that Oliver mentioned earlier.
When Oliver considers the idea, Tommy goes out to get some air and Laurel goes after him. He complains that she was trying to get Oliver to help and that it's always been her and Oliver. Laurel insists that they're over but Tommy says that he doesn't want to be reminded that he's a charity case and that Oliver can always do more for her.
After she realizes that Oliver and Laurel were once together, Helena walks out and Oliver goes after her. She figures that Oliver is still in love with Laurel and that she doesn't want to be hurt again. When he tries to stop her, Helena brushes him off and says that she's done talking.
Later that night, Tommy goes to Laurel's apartment and apologizes. She lets him in and Tommy admits that he wasn't ready to face reality. He tells Laurel that she's too good for him even before when he had money, but Laurel tells him that she never cared about the money. She apologizes for pushing him on Oliver and says that they'll handle things together.
Diggle finds Oliver at the hideout, alone, and Oliver admits that his friend was right about Helena. The bodyguard says that Helena already changed into something dark and twisted. Oliver says that he didn't want to see that and he thought he was owed something. However, he's realized that she's already gone over the edge and there's nothing he can do to bring her back.
At the docks, the Triad men are playing cards when Helena breaks in and opens fire. She kills everyone but Zhishan and he warns her in Chinese that someone seeking vengeance should seek two graves. Helena doesn't speak Chinese and shoots the man dead. She leaves one dying man with a message for the Triad saying that Frank killed them.
Walter calls Felicity in and shows her the journal. He tells her to find out everything she can about it, but warns her that his head of security died shortly after carrying out his own investigation. Felicity admits that she hates mysteries and agrees to help.
Arrow arrives at the Triad warehouse and finds the corpses, and calls to tell Diggle that they've got a war.
Frank gets word of the killing and tells everyone to prepare for war. Outside, China White and her men begin picking off the guards. One of the men runs upstairs and Arrow kills him. Gunfire breaks out and Frank runs to his safe while China and her people decimate his men. The mobster takes a journal out of the safe but China White catches up to him and prepares to kill him. Arrow arrives in time to shoot her and then tells Frank to run. As Oliver takes on more of the attackers, Frank runs out the back.
As Frank runs across the grounds, Helena arrives and shoots him in the leg with the crossbow. She tells him that it's payback for Michael, and Frank insists that he did it for the family. Unimpressed, Helena tells her father that he took everything from her so she did the same. However, as she pulls the trigger Arrow arrives and shoots the crossbow out of her hand. She walks up to him and then attacks, but the vigilante easily deflects her first few attacks. As they struggle, Frank grabs the crossbow and shoots Helena in the chest. Arrow knocks him out and carries Helena away as the police arrive.
At the hideout, Helena wakes up from the shock of being shot in the armored costume. Oliver tells her that she doesn't understand the toll that murder takes, particular when it's her father. She refuses to stop, pointing out that the police don't have any evidence, but Oliver tells her that he turned over the laptop. Helena admits that she's more interested in revenge than justice and tells Oliver to stay out of her way or she'll reveal his secret. When Oliver assures her that he did everything because he cares for her, Helena says that she can't say the same.
When Oliver shows up at her diner, Carly calls Diggle. He comes in and tells Oliver that love is about finding someone who is the right fit, not changing someone else. Oliver says that he burnt that bridge and warns that Helena doesn't see her father's imprisonment as justice. Diggle figures that Oliver has changed and tells him that when he does meet the right person, he'll be ready for her.
Felicity comes to Walter's office and turns off the lights. She shows him the journal and provides a pair of UV glasses, and a list of names is revealed.
Tommy comes to see Oliver and apologizes for overreacting. He tells his friend that he's been cut off and Oliver offers him as much money as he needs. However, Tommy says that he just wants a job because he's trying to change, and Oliver assures him that a general manager position is available. When Tommy asks about Helena, Oliver admits that they broke up but figures that she'll be back.