Nyssa returns to Starling City and tells Oliver that her father, Ra's al Ghul has given the Arrow 48 hours to find Sara's killer before he unleashes the League of Assassins.
Oliver and Diggle race to stop the Dark Archer from unleashing his vengeance on The Glades, while Oliver and Tommy's relationship takes a turn for the worse.
After the Mirakuru sends Roy into an uncontrollable rage and he unleashes on the city, Oliver realizes it's taken over completely, and he must figure out a way to stop him.
After a fight with Cyrus Gold (aka the Acolyte), Oliver is drugged and left for dead. Determined to save him, Felicity's cure causes Oliver to hallucinate, and confront his past.
Slade makes his move against Oliver - and the repercussions are enormous. While Oliver scrambles to protect his family, Isabel angles to take Queen Consolidated away from him.