Dexter appeared to be at a somewhat content place when season five of this show came to an end. There may be hope for Harrison, after all.
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It all comes crashing down on Dexter in the season five finale. The episode is titled "The Big One."
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Dexter and Quinn were at odds for most of season five. But the latter will need the former's help on the fifth season finale.
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Dexter and Masuka are seen here on the fifth season finale of Dexter. The episode is titled "The Big One."
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Dexter Season 5 Episode 12 Quotes

Don't be sorry your darkness is gone. I'll carry if for you - always. I'll keep it with mine,

Dexter [to Lumen]

Deb: You don't like Quinn much.
Dexter: I don't like him at all. But I want you to be happy.