The new spinoff, Boston Blue, has successfully brought Detective Danny Reagan (Donnie Wahlberg) into a fresh, gritty landscape, yet its success hinges on its connection to the beloved source material, Blue Bloods. Fans were thrown into a mix of excitement, confusion, and relief during the premiere, which confirmed a long-awaited romance, introduced a new actor to a familiar role, and conspicuously left out a certain Reagan patriarch.
Co-showrunners Brandon Sonnier and Brandon Margolis—often collectively referred to as “The Brandons”—have been openly discussing the strategic choices made for the new series. Their interviews have provided crucial insight into how they plan to honor the legacy of the Reagan family while carving out a new, distinct story in Boston.
Danny and Baez: The Long-Awaited Payoff
One of the most satisfying reveals for longtime viewers was the confirmation of a romantic relationship between Danny Reagan and his former partner, Detective Maria Baez (Marisa Ramirez). The Blue Bloods series finale left the possibility hanging in the air after Danny invited her out for a slice of pizza—a moment fans had theorized about for years.
Boston Blue wastes no time answering that question, showing the pair happily together, effectively closing the book on the “Will-They/Won’t-They” dynamic that defined their working relationship for over a decade.
The Long-Distance Struggle
The new drama, however, is immediately injected by the separation caused by Danny’s move to Boston. When his son, Sean, is injured in the line of duty, Danny decides to stay in Beantown, cementing his relationship with Baez as a long-distance one.
Sonnier and Margolis emphasized that this distance is not a way to sideline the popular character. Margolis stated that Baez will return “multiple times in the first season,” and her relationship with Danny will be a core storyline that explores the struggle of moving to a new place and what you leave behind.
“The struggle of moving to a new place and what you leave behind is front and center, and that includes the relationship with Baez, which continues for multiple episodes this season.” — Brandon Margolis.
This commitment to keeping the romance alive, despite the logistical challenge of the four-hour drive between New York and Boston, demonstrates the showrunners’ understanding of what was “owed” to the dedicated Blue Bloods fanbase.
The Sean Reagan Recast: A Creative Choice for a New Chapter
Perhaps the most immediately jarring change for viewers was the recasting of Danny’s youngest son, Sean Reagan. The role, played by Andrew Terraciano for all 14 seasons of Blue Bloods, has now been taken over by actor Mika Amonsen.
The showrunners offered a clear, creative rationale for the switch, emphasizing that it was tied to the character’s new professional path: joining the police force.
- New Chapter, New Energy: Margolis explained that since they are telling a “very new chapter” in Sean’s life—a police officer embarking on his career—it “creatively made sense to find an actor with a different energy.” The original actor, Andrew Terraciano, literally grew up on screen, but the showrunners wanted a new performance to help dramatize the change.
- The Heroic Launch: Amonsen’s debut was a “gamble,” opening the pilot with his character engaging in a heroic act—saving civilians from a fire—which quickly lands him in the hospital. This tragic event is what pulls Danny Reagan into the Boston world and immediately established the new actor in a role with high stakes.
- Vulnerability and Drive: They praised Amonsen’s portrayal, noting he brought a mix of vulnerability and a strong desire to prove himself, fitting the image of a rookie cop stepping into his famous family’s legacy.
While the decision to replace a beloved, long-running cast member is always risky and has drawn some fan criticism, The Brandons framed it as necessary for the new storytelling lanes of the spinoff, where Danny is now the father of a cop.
The Blue Bloods Character We Didn’t See: Frank Reagan
The premiere of Boston Blue featured a surprise appearance from Bridget Moynahan as Erin Reagan, demonstrating the show’s intent to bring back other members of the Reagan family. However, the one character viewers and Danny himself miss most is the family patriarch, Frank Reagan (Tom Selleck).
Though Frank does not appear in the pilot, the showrunners confirmed that his presence is felt and that he plays a pivotal off-screen role.
- The Guiding Hand: The dialogue establishes that Danny is in constant communication with his father, providing updates on Sean’s condition and presumably seeking his counsel. One key scene shows that Frank’s word as the NYPD Commissioner was still instrumental in getting Danny approved to work with the BPD on the central investigation.
- Maintaining The Legacy: By keeping Frank alive and active in the background, the show maintains the crucial sense that the Reagan family is still a tight-knit unit, even with Danny geographically separated. The mentions of Frank and the appearance of Erin show that the Reagan family dinner table spirit remains the moral and emotional compass for the characters.
- A Potential Return: Both the showrunners and Donnie Wahlberg himself have expressed hope that Tom Selleck will eventually make a guest appearance on Boston Blue. The door has been left wide open, with the continuous references setting up the possibility for the iconic police commissioner to eventually cross state lines.
The Boston Blue bosses have navigated the launch of their spinoff with a blend of reverence for the original and a bold vision for the future. By paying off the Danny/Baez romance, strategically recasting Sean for a new narrative purpose, and keeping the spirit of Frank Reagan alive, they’ve set the stage for a dramatic, character-driven series that feels both familiar and excitingly new.
