Angel and Laguerta aren't exactly shy about their feelings in front of Dexter. Not that it matters. He couldn't care less.
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Yes, that's Arthur Mitchell, talking to Angel in the offices of the Miami Police Department.
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Though they each have different reasons for doing so, Angel, Dexter and Laguerta are inching closer to nabbing Trinity during the episode "Hello, Dexter Morgan."
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As usual, Dexter has a great deal on his plate. He's seen here on the episode "Hello, Dexter Morgan."
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They often appear to be at odds, but Quinn and Deb actually make for great partners.
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Dexter Season 4 Episode 11 Quotes

If I can make the police think the Trinity Killer is someone else, Arthur is all mine.

Dexter

What kind of man witnesses a child abduction and doesn't call the police? Who are you, Kyle?

Arthur