Arrow Takes on the League of Assassins!

Arrow surprised fans — at least those who hadn't already been spoiled by the head of The CW, no less — with the reveal that the masked Canary taking down the scum in The Glades was actually Sara Lance (Caity Lotz), who was presumed dead after the Queen's Gambit sank all those years ago. But no one was more shocked than Oliver (Stephen Amell), who ended up stranded on an island — and apparently an Amazo freighter — for years because of the same accident.

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"It was the first time in the present day that Oliver was thrown a curveball that he wasn't expecting," Amell tells TVGuide.com. "He was absolutely positive that Sara Lance was dead. It's the first time that we've really seen Oliver thrown for a loop. As a result, he's vulnerable, which was an exciting thing for me in the episode and going forward. He has no way of dealing with Sara Lance. He has no plan. Then the revelations about where she's been and what she's capable of now, it's an onslaught of things that he is not ready for."

Since Sara Lance arrived in Starling City, the League of Assassins has been tracking her down, as evidenced by the foot soldier they sent after her whom she killed. But the League won't give up so easily. In fact, three members of Ra's al Ghul's organization come crashing back into her life this week. "They jump through his front window," Amell teases. "Of course, when he sees the League of Assassins and he sees someone dressed a member of the League of Assassins, he thinks it's Merlyn [John Barrowman], so that creates a whole other group of problems for him. It's like seeing a ghost and then you have to fight that person."

But that same spirit of Merlyn that nearly cost Oliver his life will be ever present since Al-Owal (Homeland's Navid Negahban) will be among those sent to track the Canary down. "He's formidable," Amell says. "He actually references in the episode that he's the one that trained Merlyn."

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It's the arrival of the League that, Amell says, makes this the most intense episode they've ever done. "There have been episodes with more reveals and more surprises, but top to bottom, Episode 5 is our best episode," he says. "It's a new level of action for us. I don't know what clicked, but we have three separate fight sequences that are probably the best stuff that we've done. Three of them! It's exciting."

But the episode will also have a lot of heart since Sara has refused to tell her family that she's back in Starling City. "Despite the fact that he thinks that she should, he's not going to betray her trust in that way and tell them," Amell says. "If she wants to, it's going to be her decision. We haven't really crossed that bridge yet in terms of how it will affect Oliver and Laurel [Katie Cassidy]. It certainly adds another layer into an already pretty layered situation."

Sara's past, however, is a bigger mystery which will slowly be revealed throughout the hour. For the first time, we'll actually get a flashback from someone else's perspective, as we see what happened to Sara after the Gambit sank that lead her to become the ruthless woman that she is today. Amell notes that Oliver's own time on the freighter has started to piece together the larger puzzle — which includes the hozen, the misshapen skeletons and the Russian he met last week. "We're about to find out what all of that stuff means, but the biggest issue for Oliver is that Sara is on the freighter," he says.

Arrow airs Wednesdays at 8/7c on The CW. Will you be watching?

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