Oliver faces his biggest challenge yet as mayor. Felicity continues down her dark path with Helix. After Vigilante attacks Oliver while he's acting as the mayor, Diggle leads the team in a mission to stop Vigilante once and for all.
Season 5 Episode 15 of Arrow was watched by 1,600,000 viewers, resulting in a 0.60 rating in the 18-49 demographic.
After a unhappy 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'.