The Devil You Know (S08E21)
S08E21
Frank finds himself at odds with a data-monitoring firm that declines to access a terrorist's phone, which could reveal vital details about potential attacks. Meanwhile, Erin receives a tip-off about a looming assassination from an unreliable informant.
Show
Blue Bloods
Episode
S08E21
Air Date
May 04, 2018
Season 8 Episodes
S08E01
Cutting Losses
S08E02
Ghosts of the Past
S08E03
The Enemy of My Enemy
S08E04
Out of the Blue
S08E05
The Forgotten
S08E06
Brushed Off
S08E07
Common Ground
S08E08
Pick Your Poison
S08E09
Pain Killers
S08E10
Heavy Is the Head
S08E11
Second Chances
S08E12
The Brave
S08E13
Erasing History
S08E14
School of Hard Knocks
S08E15
Legacy
S08E16
Tale of Two Cities
S08E17
Close Calls
S08E18
Friendship, Love, and Loyalty
S08E19
Risk Management
S08E20
Your Six
S08E21
The Devil You Know
S08E22
My Aim is True