Blue Bloods Season 12 Episode 10 asks tough questions about loyalty.

When Jamie's neighbor comes to him with a complaint that a bookie beat him up because he owes money, Jamie investigates. But he finds himself in a quandry when the bookie turns out to be Jamie's old mentor, Sergeant Coolidge.

Eddie thinks Jamie should look the other way, but Jamie feels that the law is the law. He tries to encourage Coolidge to quit the bookie business, but Coolidge won't. After Jamie writes his report, Sid calls him in and suggests he leave Coolidge's name out of it because Coolidge is a good cop who is trying to pay for his wife's health care.

Elsewhere, Frank and the mayor butt heads after Frank suspends a cop for starting a fight. The cop punched another officer who believes in defunding the police, and Chase thinks that since his constituents want more police presence, not less, the cop should get off. Frank tries to impress on the mayor that this isn't about anyone's political views, to no avail.

Finally, Danny isn't happy to have to team up with Waylon Gates again, especially when he realizes Gates is looking to avenge his partner's death.

To find out what happens, watch Blue Bloods Season 12 Episode 10 online.