Everyone adores David Ramsey on Arrow. Watch this video for an idea of what's to come for Diggle on the big crossover episode.
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David Ramsey gets into Diggle and Arrow Season 3 in this exclusive Comic-Con interview with TV Fanatic.
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What can Arrow fans expect as Season 2 draws to a close? David Ramsey is here with a tease.
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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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Arrow Quotes

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.

Laurel: Helena, you don't have to do this.
Helena: Yes, I do. Because once you let the darkness inside, it never comes out.