Meet the Original ‘Blue Bloods’ Reagan Family Before the ‘Boston Blue’ Takeover!

The Blue Bloods universe is growing, but fans will never forget where it all began.

On October 17, CBS will premiere Boston Blue, the highly anticipated spin-off starring Donnie Wahlberg as Detective Danny Reagan — just ten months after Blue Bloods ended its 14-season run.

Joining Wahlberg are Sonequa Martin-Green, Ernie Hudson, Maggie Lawson, Gloria Reuben, and Marcus Scribner. The new series centers on the Silver family, but before meeting them, it’s worth looking back at the Reagans, the family that started it all.

At the top of the family tree is Henry Reagan, former New York City Police Commissioner and father to Frank Reagan, played by Len Cariou. While it’s unclear if Henry will appear in Boston Blue, Cariou is keeping busy, recently joining MGM+’s upcoming comedy series American Classic alongside Kevin Kline, Laura Linney, and Jon Tenney.

Frank Reagan, portrayed by Blue Bloods lead Tom Selleck, served as NYPD Commissioner and was father to Danny, Erin, and Jamie, with his late wife Mary Margaret Reagan. Though not confirmed for the spin-off, Selleck is open to the idea — and is currently working on a new Jesse Stone film.

Danny Reagan, Frank’s eldest son, is a seasoned NYPD detective. He was married to Linda Rose Reagan (Amy Carlson) and had two sons, Jack (Tony Terraciano) and Sean (Andrew Terraciano), before Linda’s death. In Boston Blue, Danny follows his now-grown son Sean — played by Mika Amonsen — to Boston, where Sean is pursuing a career in law enforcement while putting distance between himself and the NYPD.

With a fresh setting, new characters, and the familiar grit of Danny Reagan, Boston Blue promises to honor the Blue Bloods legacy while carving its own path.