The Reagan Family Legacy Expands: 7 Original ‘Blue Bloods’ Stars Who Crossed Over to Spinoff Hit ‘Boston Blue’

The Reagan family legacy did not close its final case when Blue Bloods concluded its storied 14-season run. Instead, the iconic law enforcement dynasty expanded its jurisdiction north with the spinoff series Boston Blue, headlined by Donnie Wahlberg as veteran detective Danny Reagan. Across two seasons, seven key characters rooted in the original CBS drama have crossed paths with Danny in Massachusetts.

While some viewers assumed the spinoff would introduce an entirely disconnected universe, executive producers instead built an ongoing bridge back to New York City. Danny’s relocation to the Boston Police Department opened the door for personal reunions, active investigations, and surprise guest appearances that reward longtime fans.

From romantic developments to sibling drop-ins and behind-the-scenes directing duties, here is every original character who officially stepped into the world of Boston Blue cast lore.

Danny Reagan (Donnie Wahlberg)

Donnie Wahlberg as Detective Danny Reagan

Donnie Wahlberg anchors the spinoff, reprising Danny Reagan after playing the hot-tempered NYPD detective from 2010 to 2024. Danny trades the Five Boroughs for Boston, teaming up with fresh partner Lena Silver, played by Sonequa Martin-Green.

The move represents a significant thematic pivot for Danny, who now mentors his son on the force while adjusting to an unfamiliar department hierarchy.

“It’s not only Danny with a new partner, meeting this new family, it’s Danny being a dad and worrying about his son, making sure he gets home safe every day and teaching him the job, the way that his family taught him the job.”

Maria Baez (Marisa Ramirez)

Marisa Ramirez portrays Detective Maria Baez

Danny’s longtime partner Maria Baez made an immediate splash when the spinoff premiered, confirming a long-brewing romantic relationship right out of the gate. After initially navigating the strains of a long-distance relationship, Baez teamed up with Danny on a cross-city case during the debut season.

Their dynamic shifts into high gear in season 2. Baez formally relocates from New York to Boston, moving in with Danny and cementing their partnership outside precinct walls.

Erin Reagan (Bridget Moynahan)

Bridget Moynahan portrays Erin Reagan

Bridget Moynahan stepped back into the sharp shoes of Manhattan Assistant District Attorney Erin Reagan for multiple appearances. Erin made a guest appearance in the series pilot before reappearing later in season 1 to confront Danny about leaving New York behind.

Moynahan also contributed her creative vision from behind the camera, taking the director’s chair for season 1, episode 8.

Henry Reagan (Len Cariou)

Len Cariou as Reagan family patriarch Henry Reagan

Reagan family patriarch and former NYPD Commissioner Henry Reagan returned to offer elder wisdom. Len Cariou reprised his beloved role, showing up to support his grandson as Danny navigated a new chapter outside the New York spotlight.

“It was great to see Donnie and meet the new great-grandchild.”

Joe Hill (Will Hochman)

Will Hochman reprises his role as Joe Hill

Will Hochman, who appeared in more than 20 episodes of the original series as the son of late detective Joe Reagan, brought his complex dynamic to Boston. As an NYPD detective raised outside the central Reagan household, Joe’s presence creates an intriguing narrative foil.

Showrunner Brandon Margolis structured Joe’s appearances to parallel partner Lena Silver’s complicated family journey, helping bridge both law enforcement households.

Sean Reagan (Recast: Mika Amonsen)

Andrew Terraciano and Mika Amonsen, both of whom have portrayed Sean Reagan

Danny’s youngest son serves as the central catalyst for the entire spinoff, though with a major change behind the scenes. While Andrew Terraciano portrayed Sean across all 14 seasons of Blue Bloods, Canadian actor Mika Amonsen took over the role for the spinoff.

The Real Reason Danny Left New York

Sean takes on a far more demanding storyline than in years past. Now serving as a patrol officer in the Boston Police Department, Sean sustains an on-the-job injury—the direct inciting incident that compels Danny to leave the NYPD and transfer north to look after him.

Jamie Reagan (Will Estes)

Will Estes returns as Jamie Reagan

Will Estes rejoins Donnie Wahlberg on-screen in season 2 of the spinoff. Jamie heads to Massachusetts to visit his brother in episode 5, titled “Blood Diamonds,” where personal family time quickly spirals into an active multi-jurisdictional investigation.

Fact Check: Recasting vs. Returning Cast

A widespread misconception among viewers is that every returning character in the spinoff retained their original actor. While six of the seven returning characters feature their original talent, Sean Reagan was completely recast due to the physical and emotional demands of his expanded role on the police force.

💬 Watching the Reagan family dynamic evolve across state lines keeps the spirit of the original procedural alive while charting fresh territory in Boston.

✨ From Jamie’s guest spot in “Blood Diamonds” to Maria Baez settling into life in Massachusetts, the crossover moments continue to give franchise enthusiasts plenty to track.

📱 Which original character do you want to see visit Danny Reagan next? Drop your thoughts in the comments below!