"The Devil You Know" is the twenty first episode of the eighth season of Blue Bloods.


Frank goes head-to-head with a data-tracking company when they refuse to unlock the phone of a terrorist that may hold information regarding upcoming targets. Also, when Erin obtains information about an impending murder from a shady source, she gets Danny and Baez involved, despite the questionable agenda of the informant, and Jamie and Eddie try to locate a woman who kidnapped a newborn baby.


Detailed recap of the episode that contains MAJOR SPOILERS.
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Cast & Characters

Guest Starring

  • Bebe Neuwirth as Kelly Peterson
  • Kris Arnold as Father Denby
  • John Pankow as John Romano
  • Edward G. Betlow as Pat
  • Gil Perez-Abraham as Jorge
  • Nellie Campbell as Sofia
  • Subhash Mandal as Hamid
  • Christopher Shyer as Martin Post
  • Chazz Menendez as Flaco
  • Danielle Lee Greaves as Norma
  • Wayne Pretlow as Ted Shelton
  • Mike Donovan as John Romano Jr.
  • Victoria Blade as Alice




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Notes & Trivia


Season 8 Episodes
"Cutting Losses" "Ghosts of the Past" "The Enemy of My Enemy" "Out of the Blue" "The Forgotten" "Brushed Off" "Common Ground" "Pick Your Poison" "Pain Killers" "Heavy is the Head" "Second Chances" "The Brave" "Erasing History" "School of Hard Knocks" "Legacy" "Tale of Two Cities" "Close Calls" "Friendship, Love, and Loyalty" "Risk Management" "Your Six" "The Devil You Know" "My Aim is True"
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