David Ramsey teases a "blood quest" for Diggle in this exclusive interview with the Arrow star. It was conducted at PaleyFest 2013.
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Take note, Arrow fans: Episode 18 will be a major one. Stephen Amell explains why in this TV Fanatic exclusive.
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Arrow producer Greg Berlanti talks up The CW show in this exclusive PaleyFest interview, giving us an idea of what's to come.
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Arrow Quotes

You know Oliver, somebody once told me that secrets have weight. The more you keep, the harder it is to keep moving.

Diggle

Ra's al Ghul: You tasted death and you wanted more, but the truth is everyone and everything must come to an end. Even for one such as me.
Oliver: Kill me, but spare John Diggle's life. Let him go. I will beg for it.
Ra's al Ghul: You have shown tremendous strength, fortitude, power. No, Mr. Queen. I don't want to kill you. I want you to take my place. I want you to become the next Ra's al Ghul.