This marks the biggest episode in the history of Arrow. Find out why in this special producer's preview.
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Look who has come to Starling City. Watch this promo for Arrow and start to be very afraid for what's to come.
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Arrow Season 2 Episode 15 Quotes

Moira: What should we drink to?
Slade: To friendship.

Slade: You and I have something in common.
Moira: What's that?
Slade: I know how difficult it is to pick yourself up when other people have written you off.