Arrow battles Slade, which results in one of his friends going to the hospital. Meanwhile, Thea hits her breaking point, forcing Oliver to choose between her or Slade.
Oliver attempts to protect his family after Slade launches the next stage of his plan for revenge for Shado's death and Oliver's betrayal. However, one of Oliver's team questions whether Oliver is seeing clearly. Meanwhile, Isabel schemes to take control of Queen Consolidated.moreless
The Huntress returns to town to kill her father, who has been arrested. Oliver promises Sara that he'll stop his ex-girlfriend. However, when Huntress takes a courthouse hostage, including Laurel, Sara steps in. Meanwhile, Roy realizes the cost he must pay to keep Thea safe.moreless
A.R.G.U.S. recruits Diggle to take down a former acquaintance who is now planning to take over Afghanistan. However, he discovers that his new team will consist of three criminals that he formerly put away: Deadshot, Bronze Tiger, and Shrapnel. Meanwhile, Oliver pushes away Sara as he prepares for his battle with Slade.moreless
Oliver discovers that Slade is alive and intends to get revenge for Oliver's actions against him on the island. Meanwhile, in flashback Oliver and Sara prepares to take the Amazo, but Sara tells Oliver that he must kill Ivo to keep the doctor from revealing to Slade who is responsible for Shado's death.moreless
Oliver and Quentin try to convince Sara to stay in Starling City to help Laurel as she tries to deal with her drug addiction. However, Sara soon realizes that she is putting her family in danger when a member of the League of Assassins abducts Dinah and threatens to kill her if Sara doesn't return to the fold.moreless
Bronze Tiger escapes from prison and goes after a prototype of Malcolm's earthquake machine. Meanwhile, Roy refuses to train with Arrow unless the vigilante reveals his true identity, Laurel is disbarred, and Thea tries to get Walter and Moira to reconcile.moreless
Laurel reaches out to Arrow for assistance in investigating Sebastian Blood, but he has her arrested for her drug use when she gets too close to his secrets. Meanwhile, Roy almost kills a man when he loses control of his newfound strength. In the past, Sarah tells Oliver a secret about her older sister.moreless
A new villain, Shrapnel, arrives in Starling City and his next target is Sebastian Blood. With Arrow trapped, Diggle must try and help the alderman. Meanwhile, Thea learns about Roy's new abilities and Laurel investigates the connection between Blood and Cyrus Gold, the man who murdered her father's friend.moreless
After a battle with Cyrus Gold, Oliver is poisoned and left for dead, and Felicity gives him an antidote that causes hallucinations of his past. Meanwhile, Brother Blood captures Roy, Barry continues assisting Felicity, and Lance loses someone when he tries to run surveillance on Cyrus.moreless
Police scientist Barry Allen travels to Starling City to investigate a seemingly impossible robbery from Queen Consolidated's Applied Science Division, and Felicity takes a liking to him... much to Oliver's dismay. Meanwhile, Sin asks Roy for help tracking down a missing friend, and Thea joins her boyfriend in the hunt, only for one of them to be injured.moreless
A deadly illness sweeps through Starling City. When Diggle is struck down, Oliver confirms that the source of the illness is a new version of Vertigo. Tracking down a lead, Felicity is soon captured by The Count, who has escaped prison. Meanwhile, Moira fights for her life in the courtroom against a death sentence, and Laurel is forced to prosecute her when DA Donner is stricken down by the same illness.moreless
A.R.G.U.S. recruits Diggle to rescue Lyla, who has disappeared in Moscow following a lead on Deadshot. Oliver and Felicity volunteer to go with their friend, but run into trouble when Isabel insists on accompanying them. Meanwhile, Moira's attorney suggests that Thea stop dating Roy because it's hurting Moira's defense.moreless
An assassin attacks Queen Manor in an attempt to kill Black Canary, who has taken refuge there with Oliver's help. Meanwhile, Moira is reluctant to make a guilty plea despite Thea's advice, and Oliver is furious when he discovers that Laurel will be prosecuting his mother in court.moreless
A new crime lord, the Mayor, arrives in Starling City and starts bring in illegal guns. When Oliver tries to counter with a Cash for Guns event, Black Canary's friend sin is hurt and the female heroine sets out for revenge. Meanwhile, Diggle links up with an old friend and DA Donner asks Laurel out on a date.moreless
Officer Lance asks the Arrow for help in stopping a serial killer who goes after women, and Felicity volunteers to help. However, when their trap fails, the killer captures Laurel. Meanwhile, DA Adam Donner seeks the death penalty for Moira, and Oliver recruits Roy to help him find the Canary.moreless
Diggle and Felicity go to Lian Yu and convince Oliver to return to Starling City. Upon his return, he finds out that Isabel Rochev wants to take over Queen Consolidated. Thea is refusing to visit her mother in jail, Roy has stepped into Arrow's shoes and Laurel is trying to take down the vigilante. Flashbacks from the island show Shado, Slade, and Oliver in a difficult situation.moreless
Vampires in the area conspire to infiltrate the UTF station.
Captain Dashell looks to protect his niece from a vampire threat; The guys respond to a zombie report; John-John gets a look into Carla's personal life.
Carla goes undercover; Stubeck and Billy learn that vampires in the area are using zombies to do their bidding.
Captain Dashell and Billy go looking for the vampire who brought harm to Stubeck.
The vampire start recruiting teenagers, Stubeck and Billy learn a new technique to fight the zombies.
John-John finds out that someone from his family is a real monster.
A werewolf runs rampage during a porno shoot.
The Captain's niece is hanging out with a vampire; the Vampires in the area plan to steal bloodmobiles.
A group of teenagers go out to kill zombies ; Kristen gets invited to come out with the guys.
Billy gets kidnapped, and a zombie kill leads to disaster for one of the TV crew.