D.N. and Julie must kick it old school on the episode "CSI Unplugged" because a blackout hits the city.
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CSI Season 12 Episode 16 Quotes

Finn: You know the rule, if we don't find this kid in 3hrs, he's dead
DB: If the lights don't come back on, we'll find the kid in the dark.

Hodges: What part of "Hold the door" did you not understand?
Henry: I understood all of it.