On the episode "Road Kill," Dexter never got a chance to use this kill room. He actually ended up saving Trinity's life instead.
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What is Trinity up to? He takes Dexter along for a road trip on the episode "Road Kill."
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Dexter Season 1 Quotes

[narrated, in reference to Doakes] My devil danced with his demon and the fiddler's tune is far from over.

Dexter Morgan

There are no secrets in life, just hidden truths that lie beneath the surface.

Dexter Morgan