Frank is focused on bringing a killer to justice on the episode "Little Fish." This is a scene from the first installment of 2011.
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Blue Bloods Season 1 Episode 11 Quotes

It's the losses that keep you up at night.

Henry

Jack: What's a call girl?
Linda: That is a girl who talks on her cell all the time.
Jack: So, kind of like Aunt Erin?