Looking to expand his empire, Diaz and Laurel meet with The Quadrant, a coalition of mafia families who run national organized crime. Meanwhile, after Oliver's recent decision, Felicity and Curtis double their efforts on building Helix Dynamics.
After a violent shipwreck, billionaire playboy Oliver Queen was missing and presumed dead for five years before being discovered alive on a remote island in the Pacific. When he returns home to Starling City Oliver has been changed by his ordeal on the island. While he hides the truth about the man he's become, he desperately wants to make amends for the actions he took as the boy he was.
As the Green Arrow - a vigilante - he protects his city with the help of former soldier John Diggle, computer-science expert Felicity Smoak, his vigilante-trained sister Thea Queen, Deputy Mayor Quentin Lance, brilliant inventor Curtis Holt, and his new recruits, street-savvy Rene Ramirez and meta-human Dinah Drake.
Oliver has finally solidified and strengthened his crime-fighting team only to have it threatened when unexpected enemies from his past return to Star City, forcing Oliver to rethink his relationship with each member of his 'family'.