Billionaire playboy, Oliver Queen, has been considered dead for five years. Now, he has returned. But something, during those five years, has changed him into a mysterious green hooded archer.

Oliver's next target is Scott Morgan, a power executive who jacks up prices for electricity when people most need it. John Diggle suggests they go after the gang of bank robbers that recently wounded a police officer during a daytime heist. Oliver is not so keen but John isn't the kind of guy who gives up very easily. Oliver quickly identifies one of them as a high school acquaintance, Derek Reston - and learns that Reston may have turned to crime because of something Oliver's father did. Tommy meanwhile isn't having much luck with his hoped for romance with Laurel. He seeks Thea's advice. Flashbacks show Oliver's doubts about his survival on the island.

After taking a mob accountant's laptop, Oliver plans to return the money to its rightful owners. Felicity however finds that Dominic Alonzo - the operator of an illegal casino and the head of a gang known for kidnapping - was paid $2 million to kidnap Walter. Arrow pays him a visit and is told that Walter is dead. He tells his mother and Thea but Moira rushes to Malcolm Merlyn demanding to know why he broke their agreement. He assures her that Walter is alive and will be released as long as she continues to cooperate. Oliver is listening to the entire conversation and now knows that his mother is involved, just as Digg had warned him. Flashbacks reveal Malcolm's plan and also the the sinking of Robert Queen's luxury yacht was no accident. Laurel meanwhile tries to make up with Tommy and finally learns the real reason he broke up with her.

Laurel continues to unravel, Oliver and Lance try to convince Sara to stay in Starling City and finally reunite with Laurel and Dinah. However, Sara's fellow League of Assassins member, Nyssa, comes to bring Sara back to the fold, but when Sara refuses, Nyssa kidnaps Dinah. Realizing she's putting her family in danger by staying in town, Sara considers re-joining the league.

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.

As Oliver and Felicity look for a magical solution to defeat Darhk, a vengeance-driven Diggle gets a lead on Andy's whereabouts and heads off to confront his brother. Meanwhile, Alex takes Thea on a vacation that quickly turns into a nightmare.

Oliver wakes up to a life in which his parents are alive and he is about to marry Laurel; Felicity faces a new threat with the help of The Flash and Supergirl.

Oliver faces the forced release of criminals prosecuted by Adrian Chase, while a crate is delivered to Oliver's office containing a corpse in concrete.

Laurel learns about some damaging information that affects Emiko. Always looking to protect his sister, Oliver invites Laurel to help investigate, which makes Felicity happy as her friend is now working with the team. However, when things go awry, Felicity is forced to make a choice between the team and Laurel.

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