Gloria Reuben Guest Stars in the ‘Blue Bloods’ Finale as the Reagans Try to Save Joe Hill (PHOTOS)

Gloria Reuben Blue Bloods Season 11 Finale Rachel Weber
John Paul Filo/CBS

The two-part Blue Bloods Season 11 finale (airing on Friday, May 14, beginning at 9/8c) is going to be a very personal one for the Reagans: Joe Hill (Will Hochman), the late Joe Reagan’s son, is in serious trouble.

It all begins in “The End,” when Danny (Donnie Wahlberg) discovers that his nephew is working undercover for the ATF in an attempt to bring down a gunrunning organization. As TV Insider previously reported, Gloria Reuben is guest-starring as ATF Special Agent Rachel Weber, who’s in charge of Joe’s undercover op. (It’s a Jesse Stone reunion with Tom Selleck, who plays Commissioner Frank Reagan.)

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In the finale promo (below), Danny comes face-to-face with Joe while chasing someone. And it looks like it’s going to be Jamie (Will Estes) who worries that his nephew has been made.

The good news: Joe is a member of the Reagan family! In Part 2 of the finale, “Justifies the Means,” the brood bands together to keep him from being killed in the line of duty like his father. But Joe’s call to grandfather Frank has us worried:

Scroll down for a look at sneak peek photos from the final two episodes of Season 11, including Reuben’s guest spot and plenty of family moments. (Don’t worry — Blue Bloods has already been renewed for Season 12.)

Blue Bloods, Season 11 Finale, Friday, May 14, 9/8c, CBS

Blue Bloods Season 11 Episode 15 Danny Baez Crime Scene
John Paul Filo/CBS

Season 11 Finale Part 1 "The End"

Who’s the victim?

Joe Jamie Blue Bloods Season 11 Episode 15
John Paul Filo/CBS

Welcome back, Joe Hill (Will Hochman).

Blue Bloods Season 11 Episode 15 Frank Rachel Weber
John Paul Filo/CBS

Gloria Reuben guest stars as Special Agent Rachel Weber.

Joe Undercover Blue Bloods Season 11 Episode 15
John Paul Filo/CBS

Joe, undercover

Jamie Eddie Blue Bloods Season 11 Episode 15
John Paul Filo/CBS

Jamie (Will Estes) and Eddie (Vanessa Ray)

Will Hochman Blue Bloods Season 11 Episode 15 Joe Hill
John Paul Filo/CBS

Joe Hill

Anthony Eddie Erin Blue Bloods Season 11 Episode 15
John Paul Filo/CBS

What brings Anthony (Steven Schirripa), Eddie, and Erin (Bridget Moynahan) to the same crime scene?

Blue Bloods Season 11 Episode 15 Danny Jamie
John Paul Filo/CBS

Hope no one’s inside!

Jamie Danny Joe Blue Bloods Season 11 Finale
John Paul Filo/CBS

Season 11 Finale Part 2 "Justifies the Means"

A meeting in the middle of the night…

Frank Rachel Blue Bloods Season 11 Finale
John Paul Filo/CBS

Frank (Tom Selleck) and Rachel

Blue Bloods Season 11 Finale Danny Jamie
John Paul Filo/CBS

The Reagan brothers

Donnie Wahlberg Blue Bloods Season 11 Finale Danny Reagan
John Paul Filo/CBS

Danny’s (Donnie Wahlberg) watching someone.

Will Estes Blue Bloods Season 11 Finale Jamie Reagan
John Paul Filo/CBS

Nice disguise?

Frank Inner Circle Blue Bloods Season 11 Finale
John Paul Filo/CBS

Frank’s inner circle

Tom Selleck Blue Bloods Season 11 Finale Frank Reagan
John Paul Filo/CBS

What’s on Frank’s mind?