McGarrett and Danno get all dressed up on the episode "Malama Ka Aina." It's the third episode in the show's history.
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Looking sharp, McGarrett and Danno. The partners are nice and dressed up in this scene from "Malama Ka Aina."
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Hawaii Five-0 Season 1 Episode 3 Quotes

Thick crust. Extra bullets, please.

Danny [after seeing the markings of a gun in a pizza box]

Danny: Okay. All right. What's that look?
Steve: What look?
Danny: The look. The look you give me when you don't tell me what you're thinking and the next think I know I'm getting shot at.