Frank takes on a rape case on the episode "Privilege." The character is played by Tom Selleck.
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Jamie Reagan is to to the police force. But he comes from a very long line of family cops.
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Donne Wahlberg plays a main role on Blue Bloods. He's seen here as the character of Danny Reagan.
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Blue Bloods Season 1 Episode 3 Quotes

No, you're suppose to hit the other guy in the head.

Henry [to Jamie as he is practicing flipping his nightstick]

Right now, your case is weaker than the Mets bullpen.

-Detective