The episode picks up exactly where last week left off, with Sara dying in Laurel's arms in an alley.
The next morning at the abandoned Verdant, Roy and Oliver are asking Felicity to rework their phone system. They head down into the Foundry, where Laurel has brought Sara's body and left her on the table. With everyone else in denial around him, Oliver closes Sara's eyes and hugs Laurel.
Cut to Hong Kong, where Oliver, dressed like a homeless man, is walking with Maseo, who assembles a rifle and tells Oliver that Waller obviously needs him for something, and because he's been acting up, Oliver will now have to conduct a hit for her. He looks through the sight of a sniper rifle at the target -- Tommy Merlyn.
Back in Verdant, Laurel is reminiscing about Sara and her childhood stuffed animal -- a shark from the Starling Aquarium. She wants to find it now that Sara is dead. Oliver promises that he's going to find the killer, and Laurel says she will join him. Oliver pulls up a chair to try and dissuade her, but she doesn't want to tell Lance until they find the killer because of his health. She leaves, saying she shouldn't be at a bar.
Oliver calls Thea, leaving her a message that he really wants to hear her voice.
When Felicity can't get anything useful off security cameras, Oliver goes to the scene of the crime to find evidence. He discerns the trajectory of the shots and is approached by Diggle, who asks if he's okay. Oliver won't answer, and remains all business. Diggle tells him that he won't let Oliver go after the killers alone. His phone rings and it's Felicity, saying that Lance wants to see the Arrow.
It's not about Sara, though; it's about someone else, a financier from Qurac, who has been killed by an assassin using arrows. Lance can tell something is wrong, but Oliver doesn't tell him what; he tells Arrow to watch his back.
In a building under construction, a black-hooded archer kills another man, firing an arrow through several panes of glass along the way.
Back at the Foundry, Roy and Felicity are doing an autopsy while Felicity remembers Sara and her feelings of envy that Sara seemed invincible. She answers a phone call, telling her boss there's been a death in the family.
Oliver enters, telling Diggle that there are only ten or so archers he knows of who can do this -- most are in the League of Assassins. He says they don't target their own, though.
Felicity calls up security footage of the killing at the construction site, and while the archer has stayed out of sight for the duration of the assassination again, this time there may be witnesses. Oliver asks Diggle to get A.R.G.U.S. access from Lyla to help with the investigation. After Diggle leaves, he's upset that Thea hasn't called back yet.
In Hong Kong, Oliver refuses to take the shot at Tommy. Maseo says that Waller needs Tommy dead because he's in Hong Kong looking for Oliver, since he set off an alert by logging into his e-mail account.
Back in the Foundry, Roy is looking for Thea by hacking into an FBI database. He still hasn't told Oliver about the note she left him when she left five months ago. Felicity tells him taht he needs to show Oliver.
Her phone goes off, and she leaves, saying there's someone she needs to kill. She goes to Queen Consolidated, where Ray Palmer is holding some kind of event. He's been stalking her, including buying the electronics store where she works. He tells her that she can either work for him at Queen with an office and a big salary, or at the electonics store. She tells him she won't do either and quits, but he stops her on the way out, detecting that there's something wrong with her not to do with him and offering to talk with her about it. When she won't, he says that he's sorry for whatever's hurting and that it gets better.
Back at the construction site, Arrow arrives to find the drug dealer who had been squatting there trying to run away. He roughs the guy up a bit, demanding to know what he saw. The dealer says the bad archer was wearing a black facemask. Diggle says his name is Komodo. He's wanted for murder already in seven countries.
Felicity figures out a way to track Komodo's phone, which Oliver uses to chase him down and prevent a hit he was attempting on a man whose car he crashed. The two square off, shooting arrows at one another from motorcycles, going in laps like a joust. Ultimately Oliver is hit and Komodo takes his motorcycle to escape, btu the bike has a gas leak. Back in the Foundry, Laurel is angry.
Oliver comes to the Foundry, where Oliver asks about the driver -- he's out of the hospital -- and about Simon LaCroix (Komodo). They start trying to work the connections between his targets.
Back in Hong Kong, Oliver insists there has to be another way. Maseo says that there is, but it involves Waller finding another killer.
At his rent house, Tommy has a fight on the phone with his father, and then is grabbed from behind and stuck with a hypodermic.
In the hospital room of Ehrlich Kelso, the man Komodo almost killed, Laurel shows up, demanding entry because she's from he DA's office and her dad is the captain. Protective custody relents and she goes in, closing the door behind her.
At the Foundry, Oliver is impatient with how long Felicity's algorithm is taking to run, and tells her that he needs her A-game. She tells him she doesn't have it -- that their friend was just murdered. She tells him that she's sorry she has feelings, but maybe if he did too... She asks how he can be so cold when Sara's been killed. He tells her that everyone looks to him to lead and he doesn't have the luxury of grief. She tells him that he's still human, and that she knows it's easier to avoid them by hiding behind Arrow. He tells her that earlier today, he was looking at Sara and realized that eventually it will be him who's killed doing this -- that it's the life he's chosen. Felicity says she won't wait in a cave to die with him; she says life is precious and she wants more than this. She leaves, in tears.
Laurel asks Kelso why someone would want to kill him. When he won't answer, she gets aggressive. When he objects, she re-breaks his arm on the side of the hospital bed and demands answers, asking him what he has in common with the other men who were killed. he admits they were all working on a secret deal together to build an oil pipeline for Ameritek. An arrow comes through the window and kills him.
Back at the Foundry, Oliver calls Thea again. Diggle says Lyla has multiple teams trying to track LaCroix. He asks what Oliver needs, and he says Thea. Roy tells him that's not going to happen, and Oliver asks why. Roy gives him the note, explaining himself and apologizing. Oliver just says "okay."
At the hospital, Laurel calls Felicity and leaves a message. Lance comes and tells her to go home and be safe -- that Sara takes enough chances for the both of them. Her call comes in from Felicity, and she heads to the Foundry, where they figure out that the deal was to open a pipeline in Qurac. There were secret bribes given to the three victims by Ameritek's Tom Weston, who will be LaCroix's next target.
Laurel storms off, saying she's coming with him and grabbing a gun, which Oliver takes from her. He tells her to stay behind promises he won't let Komodo escape again. That night at Queen, Ray Palmer's soiree is where Weston can be found. He's introduced to the room and makes a speech, urging his fellow rich guys to help the city they live in. Palmer says he'll give away half of his fortune to the less fortunate of Starling, and that he'll have a $1 salary for the year. As he finishes his speech, Komodo crashes in through a wall and snares Weston. Arrow and Arsenal crash in after him and the three fight, with Komodo finally leaving through the window and Arrow chasing. They banter briefly before Arrow shoots him through the chest. While he's trying to extract information from Komodo, Laurel shows up with a gun. He tries to talk her down, but she's not having any of it. Eventually he realizes that she thinks he killed someone he didn't, and tells her that two nights ago he was drunk in Bludhaven. Eventually Laurel pulls the trigger, but the gun is empty. They leave Komodo, stuck to a pillar, as police helicopters circle.
Back at Verdant, Oliver tells her that LaCroix's alibi checks out. He tells her that her father deserves to know, since without this answer, they don't know when the case will be solved. She goes to the police station, where her father is on the phone talking about LaCroix. She tells him that she lied to him at the hospital last night, and he deserves to know the truth. Before she can tell him, though, he has a device that beeps and reminds him to take pills for his heart. That night, Team Arrow buries Sara in her old grave and has a private, quiet service. At the end, Laurel objects, saying that it's not fair nobody will ever know who Sara was. She breaks down in Oliver's arms. Diggle tells her that they'll know -- and that they're naming their daughter after Sara.
In the flashbacks, Tommy awakens tied to a chair and surrounded by bright lights. Oliver is wearing a black outfit; he says that he hacked Oliver's account to lure someone to kidnap. He tells Tommy that Oliver is dead, and Tommy will be too if Malcolm doesn't pay a ransom. He steps away for a moment and Maseo storms in dressed as a cop and frees Tommy.
Back at the Foundry, Oliver is sitting alone in the dark when Diggle comes. Ollie says he's going to catch the killer and Dig says he knows. He says that he's back on Team Arrow until they do -- that Sara is family too. Oliver says now he has to go find Thea. Diggle starts to leave, but Oliver stops him, saying he doesn't want to die down there in the Foundry. Diggle says, "So don't, Oliver."
At home, Laurel is curled up with Sara's stuffed shark and the Canary jacket she was given at the end of last year. Diggle is looking into the baby's bassinet and smiling. Roy is looking at a phto of Thea on his phone. Felicity heads to Queen to tell Palmer she'll work for him, saying that she wants more out of life.
Cut to Corto Maltese, where we see three robed figures sparring. One of them defeats the other stwo handily, and then removes a mask to reveal Thea, who thanks "dad," Merlyn, for his applause.