Through the Looking Glass - S5-E19
Other mistake: Danny supposedly handcuffs an at-risk teenager. When the police officer takes her away to a cell, the girl isn't handcuffed. The handcuffs are just in her hands behind her back. (00:52:00)
Blue Bloods (2010)
1 other mistake in season 5
Starring: Tom Selleck, Bridget Moynahan, Donnie Wahlberg, Len Cariou, Will Estes
Dedication - S1-E15
Continuity mistake: At the start, Frank isn't wearing glasses at the table. Then in one shot he is. Then not again. (00:00:40)
Frank Reagan: I'm the PC. I know everything.
More trivia for Blue Bloods
Question: What is the pin Mayor Dutton is wearing?
Answer: The Seal of the City of New York.