Sworn to fight crime and corruption in his city, Oliver Queen (aka The Arrow) – with the help of his iron-fisted right hand, John Diggle, the tech-savvy Felicity Smoak and newest member of the team, Roy Harper – narrowly defeated the vengeful Slade Wilson (aka Deathstroke), his onetime ally and mentor. But Season Three brings another lethal face from his past – Ra's Al Ghul!