Arrow moves further along his father's list while battling family issues with his mother, Moira, and especially with his sister. He also makes amends for past difficulties with Laurel.

A new vigilante is killing off the people that work for mob boss Frank Bertinelli.

Oliver Queen attempts to train Helena Bertinelli in the hopes that she will join him in his fight for justice. Meanwhile, Walter Steele delves deeper into his wife's secrets.

A jewel thief named Dodger strikes Starling City, a purse snatcher targets Thea and dating anxiety hits Oliver and Diggle. Each perilous situation leads to hard choices.

The plan to kill Malcolm Merlyn goes into operation. Arrow kills one assassin who has just arrived in the city and retrieves his cellphone. It's up to Felicity to break into it and find out just who the target is. A birthday dinner for Tommy Merlyn is interrupted by his father who brings him a present. Tommy makes it clear that he is not welcome and does not want a relationship with him. Malcolm is to receive an award at a civic gala and after a heart to heart with Oliver, Tommy decides to attend. When Oliver learns that Malcolm is the target, he races to save Tommy. Once the attack begins, Malcolm and Tommy takes refuge in his office and Malcolm is about to reveal that he is the Dark Arrow but is seriously wounded before he can do so. Arrow arrives on the scene and to convince Tommy that he is there to help, reveals his identity.

Now that Oliver no longer has the list to work from, he's not sure what's next. Roy continues doing his own vigilantism and has to be bailed out of jail by Thea. When he mentions to Oliver that someone is hijacking medical deliveries to the Glades Memorial hospital, the Arrow knows exactly what he wants to do. His visit to the hospital doesn't go well when local politician Sebastian Blood takes him to task for what his family has done. When he tries to stop a hijacking, Arrow comes up against China White and her new partner Bronze Tiger. Thea tells Roy she's not going to wait around until he gets killed. The flashback to the island shows the aftermath of Oliver's violent attack on the unknown visitor. Shado takes him in hand.

The League of Assassins give Oliver 48 hours to find Sara's killer, or Starling City citizens will die. Oliver then has an epic confrontation with Ra's al Ghul.

Arsenal and Diggle confront Laurel about trying to step into her sister's shoes and warn her to stop before she gets herself killed. However, the villan Brick kidnaps the city's Aldermen and threatens to kill them all unless the police evacuate The Glades, it's all suits on deck. Meanwhile, Ray steps in to help Lance and the police force fight Brick, showing Felicity a new side of her boss. Malcom tells them that Ra's al Ghul is after his family and they must leave town immediately.

Malcolm puts Oliver and Thea in a dangerous situation that lands them on Lian Yu with Oliver's former enemy, Deathstroke. A flashback reveals when Oliver and Maseo returned to Starling City to retrieve the Omega bio weapon, and despite being under strict orders from Amanda Waller not to reveal himself to anyone, Oliver looks in on his family, Laurel and Tommy.

Three of Oliver's old foes break out of prison and form an alliance; Meanwhile, Lance is confronted about an old partnership.

The past comes back to haunt both Oliver and Laurel. Curtis is upset when he discovers that Diggle and Lyla have restarted The Ghost Initiative with Diaz, China White, Kane Wolfman and Carrie Cutter.

After months of covertly pursuing Dante, Diggle and Lyla finally have a solid lead on the elusive terrorist, so they deploy the ARGUS Ghost Initiative to apprehend him. Meanwhile, Oliver tries to bond with Emiko.

Oliver, John, Laurel, and Tatsu seek out an important person within The Monitor's plan. Connor has a heart to heart with his brother.