A new crime lord, The Mayor, plans to take over Starling City using stolen military weapons. While the Hood tries to stop him, he encounters Black Canary and discovers who she really is. When The Mayor injures Black Canary’s sidekick Sin, the female vigilante joins forces with the Hood to take the gunrunner down. Meanwhile, Quentin confronts Diana about her drinking problem, and in the past, Oliver is interrogated about the corpses on the island.
Watch It Here : Arrow Season 2 Episode 4