The episode opens on a group of goons in a warehouse, who are taken out by a S.W.A.T. Team led by a female cop. A pair of plainclothes cops come in, and when they try to stop what she's doing, she takes them down, too.
Later, Thea and Laurel are arguing about telling Oliver about Sara. Laurel doesn't want him to know. Diggle joins them, saying that Oliver has a big announcement, and when he shows up with Felicity, Thea assumes the two have become engaged. Oliver tells them that he's decided to run for mayor -- and Team Arrow is non-plussed.
In the basement of the campaign office -- which used to belong to Jason Blood -- is a new Arrow Lair, designed by Cisco and S.T.A.R. Labs. Felicity hears of the cops who were found dead, and Diggle is going to head off to look for evidence. Oliver is going to talk to Lance.
Lance is taken up with the shooting, when Oliver shows up to talk to him, and tells him that he's decided to run for mayor. Lance leaves when he gets a text from Laurel, and Oliver takes the evidence to process.
In the flashback, Oliver helps the woman he rescued last week, giving her a shelter and tips on how to hide out. He has a plan.
In the present, Holt is trying to figure out who the Green Arrow is. Felicity asks him to help her find who hacked her phone. He says it wasn't him, but it looks familiar. It reminds him of some code of Ray's. He recorded a statement before his death, but Felicity doesn't really want ot see it.
At the Lair, Oliver gives Felicity a SIM card he got from the crime scene. She triangulates where it came from based on previous locations, and Team Arrow suits up to go there. It's empty, except for one room where there's no people, but an armory. He finds body armor belonging to the police and figures out there are dirty cops killing people.
Laurel takes Lance into the basement of her apartment building, where a Feral Sara is chained to a post. He's confused as to what happened, and he's traumatized at seeing what Sara has become. Laurel tells him it will be okay. When Sara grabs Laurel, he pushes her off.
Back at the Lair, Oliver and company talk about the dirty cops and how to find drug dealers. Thea and Diggle head out undercover to a nightclub, and start asking around.
Back at the police department, Lance is at his desk when Oliver comes to tell him that it was dirty cops, not gangs, who killed the detectives. Lance wants to be there when they lure the dirty cops in.
In the flashback, Oliver blames the other soldier's death on another land mine, and one of the others doesn't believe him and insists on seeing the woman's body.
As Diggle and Thea wait for the dirty cops, Arrow alerts Lance to a coming vehicle. A firefight breaks out between Team Arrow, the S.W.A.T. Officers, and Lance. The Lady Cop from beore brandishes custom blades, but it's brief. They leave without the drugs but Team Arrow doesn't get them into custody, making the trap kind of a bust.
Back at the Lair, Lance is pretty upset about the fact that they've already back up and running, tech-wise. He admits that the anti-vigilante task force had the kind of high-tech gear the dirty cops were using, and offers to share precinct resources with Felicity to speed up the investigation.
The Task Force guys want to kill Lance, but Lady Cop rejects the idea, saying she can use him.
Holt has been trying to get hold of Felicity, telling her that he's almost found Ray's final message. She tells him no, that she doesn't want to hear that. Holt says his brother died a few years ago and he would kill to hear his voice again.
Later that night, Damien Darhk and Lance are talking. He tells Darhk about Sara's resurrection, and asks for his help with her. Darhk says that if it were his daughter, he'd put her down -- that it isn't Sara anymore.
At the Lair, Felicity names Liza Warner as the Lady Cop. She's been depositing large sums into offshore bank accounts. She's trying to use dashboard cams to recognize her. Oliver, though, sees Lance talking to Damien Darhk.
When Lance comes home, Oliver is waiting for him to confront him about his dealings with Darhk. The two argue. Oliver tells him that he's the reason Ollie decided to run for mayor; he wanted to impress Lance, but now he's just sickened by him.
In the flashback, the soldier following Oliver tells him that there's something dark inside him, and that he can tell it isn't Ollie's first kill. He says he's the same way, and Ollie will find out, if he's lying.
In the present, Oliver tells Thea that he wanted to be the person who united Star City, like when they were at ballgames as kids. He thinks the city might be beyond saving, and that he doesn't have to run.
In the basement of Laurel's apartment, the chained-up Sara is looking at old photos. Lance comes to shoot her. Laurel stops him, and the two cry together before Lance runs off. In the hallway outside his apartment, the dirty cops are waiting for him. Warner beat shim up while two others hold hm, then Laurel comes and beats a couple of guys in the hallway before they taze her, take Lance and run.
Lady Cop takes Lance to her little base, where she believes she isn't a criminal They've set his biometrics up to open the door -- which is fine, because that means Felicity can see where he is. Lady Cop and her goons are taking all the contraband they can carry and leaving, but Team Arrow shows up to stop them. Green Arrow frees Lance, who Warner had tied up, and the two groups fight.
At some point, Warner gets a leg up on Oliver, putting a knife in his back and threatening to sever his spinal cord. Lance talks her down, appealing to her sense of justice, and he arrests her.
Back at Lance's apartment, Oliver asks him if he really believes in what he said to Warner. Rather than turn himself in, Oliver asks Lance to help him get close to Darhk.
In the flashbacks, Oliver brings the soldier to see the woman, whose corpse is still in the cave where he left her. He brings her "back" with a quick flip of the wrist and tells her he learned it on the island. Outside, the soldier finds Oliver's A.R.G.U.S.-issued laptop
At his campaign office the next morning, Oliver comes in to find the place staffed up. Thea had brought them in to work, and wrote Oliver a speech -- which he delivers soon after.
While he's doing so, we cut back to Oliver listening to Ray's message (she's at the speech, too; it's just editing).
In the basement of her apartment, Laurel goes to see Sara and she has escaped.