Team Green Arrow's ongoing battle with Damien Darhk is complicated by a shocking revelation. Thea's bloodlust returns and she loses control in front of Alex.

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.

A deadly new criminal, Tobias Church, threatens Star City, which forces Oliver to consider forming a new team of superheroes to help him do battle. In flashbacks, Oliver faces off against the Bratva in Russia.

Oliver recruits Curtis, Wild Dog and Evelyn Sharp for his team, but his training methods prove to be too much for some to handle. In flashbacks, Oliver continues his initiation into the Bratva.

Oliver wakes up to a life where he never got on The Queen’s Gambit. Robert and Moira Queen are alive and well. Laurel is his loving fiancée and their wedding is imminent. Everything seems perfect, but Oliver starts to notice small imperfections that make him question this new reality. Meanwhile, Felicity and the recruits take on a new threat with help from The Flash and Supergirl.

The crossover starts on Supergirl S02E08 Medusa (I) and The Flash S03E08 Invasion! (II). It continues on DC's Legends of Tomorrow S02E07 Invasion! (IV).

Oliver deals with the fallout of the explosion on the island.

Barry and Iris’s wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth’s mightiest heroes – Green Arrow, Supergirl, The Flash and White Canary – lead their teams into battle to save the world.

The crossover starts on Supergirl S03E08 Crisis on Earth X (I). It continues on The Flash S04E08 Crisis on Earth-X (III) and DC's Legends of Tomorrow S03E08 Crisis on Earth X (IV).

Despite losing half his team, Oliver remains confident that he, Felicity and Diggle can stop Cayden James and Black Siren. However, when he discovers one of Cayden’s secrets, he decides to team up with an unlikely ally. Meanwhile, Dinah spends time with Vince.

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

Following Oliver’s shocking decision to turn himself over to the FBI and reveal his identity as the Green Arrow to the public, Oliver has spent the past five months in Slabside Maximum Security Prison. Determined to keep a low profile to shorten his sentence for the sake of his family, Oliver is tested when he runs into old foes. Meanwhile, Diggle and Dinah have taken on new jobs and left their costumes behind but not everyone is following suit. With her focus on William, Felicity tries to start over but when someone from her past resurfaces, things become complicated.

Oliver makes a choice that will affect his entire life, as well as the lives of everyone he cares about.

With Oliver and Barry still stuck in the other’s bodies, the two get a lead on John Deegan and head to Gotham City with Supergirl to figure out why their reality has changed. While there, they meet the mysterious Kate Kane who provides them with information that leads the group to Arkham Asylum.

The crossover starts on The Flash S05E09 Elseworlds (I) and concludes on Supergirl S04E09 Elseworlds (III).

Mia and William venture into the Glades on a dangerous mission. There they run into Dinah, Roy and Zoe who deliver some devastating news. The flash forwards share highlights from Mia’s childhood with Felicity.

The battle between Oliver and Emiko comes to a boiling point which brings back some familiar faces and leaves others in dire jeopardy.

Oliver returns to Starling City on Earth-2, where he encounters familiar faces while trying to decipher the Monitor's mission. Meanwhile, Mia and William's team clash with a new foe.

Oliver's mission takes him to Lian Yu where he tries to ignore the repercussions of the looming Crisis until he receives help from an old friend. Meanwhile, a united Team Arrow faces a recognisable villain.

After eight seasons, and the launch of countless superheroes, the series wraps up the story of the Green Arrow.