Blue Bloods Spinoff Shakes Up Cast with Surprise Recast

In a surprising move, the Blue Bloods spinoff series Boston Blue has recast the role of Danny Reagan's son Sean. The character, who was played by Andrew Terraciano throughout the original show's 14-season run, is now portrayed by a new actor, Mika Amonsen.

The decision to recast the role has sparked some controversy among Blue Bloods fans, who have grown attached to Terraciano's portrayal of the character. However, Boston Blue's showrunner, Brandon Margolis, has defended the move, stating that it was a "creative" decision to bring "new energy" to the character's storyline.

Margolis explained that the writers' room was looking forward to exploring "new storytelling lanes" with the spinoff series, and the recast of Sean Reagan was an "organic opportunity" to do so. He praised Amonsen's performance, noting that the new actor has brought a sense of "vulnerability" and a "desire to prove himself" to the character.

The spinoff series, which premiered in 2025, follows Danny Reagan (Donnie Wahlberg) as he takes on a new position with the Boston Police Department. The show also features a new detective, Lena (Sonequa Martin-Green), who becomes Danny's partner. With Sean Reagan now joining the family business, the series promises to explore the dynamic between the father and son in a fresh way.