After Detective Lance arrests Oliver for murder, Oliver tells Moira the only lawyer he'll allow to represent him is Laurel. Laurel takes the case which puts her at odds with her father. Oliver offers to take a polygraph in front Detective Lance but things get tense when Lance asks him if anyone else was on the island with him. Oliver flashes back to when he got his first scar, courtesy of Deathstroke.

Thea is in trouble with the police after she gets caught using a drug called "Vertigo." Oliver thinks the only way to keep her out of jail is to find the dealer, a man who goes by the name of "The Count". Oliver turns to McKenna Hall, an old flame and current Vice cop, for help. Meanwhile, Laurel steps in to defend Thea, and Felicity gives Oliver some disturbing news about Moira.

An angry resident of The Glades who calls himself "The Savior" embarks on a kidnapping and killing spree to punish those he believes have wronged the residents of his neighborhood. To make things worse, he broadcasts these murders online and claims he was inspired by Arrow's vigilantism. Oliver is horrified by this statement and vows to stop "The Savior," but his manhunt in intensified after Thea comes to him in tears and tells him Roy has been kidnapped. Laurel is surprised when her father starts to believe her mother's claim that Sara is still alive. Meanwhile, Malcom tells Moira to find the person responsible for his attempted murder.

With the Undertaking days away, Malcolm dons his black hood to conclude business with seismologist Dr. Brion Markov and his team. Oliver and Moira entertain a number of surprise - and mostly unwelcome - visitors. Hooded confrontations at home and the Meryln Global Group reveal dark secrets. Meanwhile, Roy and Thea are still looking out for a hero. Laurel makes a decision after Tommy's revelation. In a flashback to the island, Oliver, Slade and Shado struggle to prevent Fyers from shooting a Ferris Air jet out of the sky. Paul Blackthorne and David Ramsey also star.

Oliver discovers a man who goes by the name “The Mayor” is bringing illegal guns in to The Glades, so Oliver sponsors a “Cash for Guns” event to help clean up the city. Unfortunately, The Mayor crashes the event with his gang and seriously injures Sin. The Canary is furious when she learns her friend is in the hospital and sets out for revenge. Meanwhile, Felicity stuns Oliver with a bit of information about the Canary, Donner asks Laurel to dinner, and Diggle reconnects with an old friend.

Roy Harper came to meet Oliver Queen but Felicity Smoak tells him to wait as Oliver is not available.

Detective Lance calls Felicity telling her that SCPD Laboratory is having blood samples of The Arrow then Felicity gives Roy Harper a job to break in SCPD Laboratory and get the samples.

Roy Harper breaks in SCPD Laboratory to get blood samples of The Arrow.

Felicity Smoak helps Roy Harper escaping SCPD Laboratory.

Roy Harper escapes SCPD Laboratory getting the blood samples of The Arrow with the help of Felicity Smoak.

Roy Harper gives the blood samples to Felicity and felicity allows him to meet Oliver Queen.

When her father won't believe her accusations against Sebastian, Laurel turns to the Arrow for help. Oliver has his own doubts about Laurel, particularly when she is arrested on a charge of drug possession. Meanwhile, Roy sets out to test his new abilities but goes berserk, putting a man in the hospital.

A master hacker dubbed Clock King coordinates a series of raids on banks in Starling City, and his skills prove a match for Felicity. Meanwhile, Laurel's grudge with Sara continues and on the island, a pilot crashes his plane there and Sara tends to the dying man.

The Mirakuru sends Roy into an uncontrollable rage and he unleashes on the city. Oliver realizes the Mirakuru has taken over Roy completely and must figure out a way to stop him.

Nyssa believes that Malcolm killed Sara and goes after him to avenger her lover's murder. Oliver discovers that he has no choice but to stop her, despite Laurel insisting that he avenger her sister's death. Meanwhile, Thea returns to Starling City and settles in... until Nyssa discovers that she's Malcolm's daughter.

The Arrow is stalked by an ex-police officer who he rescued during the Mirakuru siege and has become dangerously obsessed with the hero. Meanwhile, Ray asks Felicity to accompany him to a business dinner, and Thea is forced to hire a new DJ for Verdant.

Brick takes three city aldermen hostage and demands that Mayor Castle turn the Glades over to him in return for their safe return. Meanwhile, Felicity turns to Ray for help when she needs a helicopter, and Laurel realizes that she may be in over her head with her new crime fighting carer.

Ra's makes his next move against Oliver by reveling the Arrow's secret identity to Quentin. Left without alternatives, Oliver has no choice but to surrender. Meanwhile, Ray is injured in an attack and Felicity must take a risk to save his life.

Oliver has no choice but to accept Ra's's offer to resurrect Thea. In return, Oliver must become the Heir to the Demon.

The growing tension between Oliver and Diggle puts both their lives at risk when they go after Damien Darhk and a H.I.V.E. deployed meta-human. Meanwhile, Laurel talks Thea into returning to Nanda Parbat to ask her father to put Sara into the Lazarus Pit. However, Laurel is surprised when Nyssa refuses to do it.

After the city is attacked again, Oliver makes a bold move against HIVE. Malcolm checks in on Thea and leaves her with a warning. Things take a horrible turn when Damien Darhk retaliates in a brutal manner at Oliver’s mayoral holiday party.

Oliver and team uncover HIVE’s plan to take out Team Arrow once and for all. With HIVE’s next attack imminent, Lance wonders if Donna is safer without him in her life. Meanwhile, with the wedding fast approaching, Oliver begins to feel guilty that he hasn’t told Felicity about his son.

Oliver and the team struggle to come to terms with Laurel’s death, especially Diggle who is overwhelmed with guilt for choosing to believe Andy had changed. Meanwhile, Lance refuses to believe his daughter is really gone and asks Nyssa to help bring her back. A recent Black Canary sighting in Star City only seems to prove his theory that Laurel isn’t actually dead.

Prometheus claims two more victims, and Oliver realizes that the killings are related to the people on his father's list. His recruits aren't happy to hear that Oliver used to be a serial killer. In the past, Oliver finally meets Kovar and may not live to regret it.

After Prometheus attacks Curtis, Oliver realizes Prometheus knows all of Team Arrow’s secret identities and is planning to come for them one by one. Felicity and Detective Malone discover a clue that links Prometheus to Oliver’s past.

Oliver and Felicity get trapped in the bunker together, while Diggle and Lyla deal with marital issues.

Oliver assembles a group of unlikely allies - Slade, Nyssa, Merlyn and Digger Harkness - to engage in an epic battle against Chase and his army.

Oliver celebrates Thanksgiving with his family but the happy moment is interrupted. Meanwhile, Black Siren returns to wreak havoc on the holiday.

Oliver turns to an old friend to help battle Diaz; Rene is out of the hospital but has a hard time readjusting to life as Wild Dog; Lance discovers something shocking about Black Siren.

With a new ally on his team, Oliver engages Diaz in an epic final battle.