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

Tonight's the night. And it's going to happen again, and again. It has to happen. Nice night.

Dexter Morgan

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

Dexter Morgan