Major update for Blue Bloods fans. CBS is officially recasting Danny Reagan’s son, Sean, in the new Boston Blue spin-off series . Just one day after Donnie Wahlberg posted a behind-the-scenes photo from the first table read, this announcement was made.
Andrew Terraciano, who portrayed the character for over a decade on Blue Bloods, will be replaced by Mika Amonsen to play now play Sean Reagan. The switch marks a significant change for viewers who have grown up watching Sean’s character evolve on-screen.
A New Actor Steps Into a Familiar Role
Sean Reagan, the son of Detective Danny Reagan, is a familiar name for longtime fans. But in Boston Blue, CBS is taking the story in a fresh direction. According to the network, Sean will now be a young Boston Police officer, working alongside his father in a new city with a different police culture.
The role was recast quietly, with Mika Amonsen stepping into the spotlight. The decision is already sparking debate among viewers, many of whom are surprised that Andrew Terraciano didn’t return. His absence is noticeable, and CBS has yet to release a statement explaining the change.
Donnie Wahlberg Hints at a “New Chapter”
On July 8, Donnie Wahlberg shared a behind-the-scenes image from the first official table read for Boston Blue. The photo featured his script and a caption that read, “A new chapter.” It’s clear the show intends to push boundaries and move beyond the structure of Blue Bloods, which ended its 14-year run in late 2024.
So far, Wahlberg is the only confirmed original cast member returning. However, fans are hopeful for guest appearances from familiar faces — including Tom Selleck, Bridget Moynahan, and Will Estes.
What We Know About Boston Blue So Far
The new series will air on Fridays at 10 p.m. ET as part of CBS’s 2025–2026 lineup. The cast features several new names alongside Wahlberg and Amonsen:
- Sonequa Martin-Green as Detective Lena Silver, Danny’s new partner.
- Ernie Hudson, Gloria Reuben, Maggie Lawson, and Marcus Scribner as members of Lena’s law enforcement family.
The show aims to blend new character arcs with the legacy of the Reagan family. But with most of the original cast absent, viewers are left wondering whether this is truly a continuation or a total reboot.
Are More Reagans Coming?
Donnie Wahlberg has teased the possibility of cameos. In a recent interview, he said that while Boston Blue is “its own show,” it’s still “deeply connected to the Reagan legacy.” CBS has not confirmed any additional returning actors, but fans remain hopeful that the family dinner table might return — even if just for a single episode.
With Mika Amonsen now cast as Sean Reagan and filming already underway, Boston Blue is moving forward fast. But whether the show captures the same magic as Blue Bloods remains to be seen. For now, fans are adjusting to the idea of new faces playing old roles — and waiting to see if their favorite Reagans will return to the screen once more.
