Blue Bloods spin-off recasts long-running character from original show to join returning fan favourite

It's been announced that the character of Sean Reagan won't be played by Blue Bloods actor Andrew Terraciano, but will instead be taken over by Mika Amonsen.

The recast is said to be because of the new creative direction of the series, which will see Sean follow his father's work in law enforcement.

The series will be led by Donnie Wahlberg, who reprises his Blue Bloods role as Danny Reagan, previously working in the NYPD but now making the big move over to Boston for a monumental new chapter.

The addition of Danny's son Sean to proceedings is said to help explain Danny's move from New York to Boston, with Sean being seen in the Blue Bloods finale getting prepared to go to college. So, what has spurred on the career change?

According to Deadline, Boston Blue will see Sean starting up as a Boston PD patrolman. Wanting to continue his family's law enforcement legacy but wanting to do so outside of their native New York, he decides to go to Boston for pastures new.

But when Danny also decides to stay in Boston, it gives the pair a chance to strengthen their father-son relationship.

As for Amonsen, he has previously starred in an episode of Apple TV+'s Pachinko, Suits and Designated Survivor, as well as 2023 slasher Thanksgiving.

The original series saw the role of Sean played by Terraciano, with the other Reagan son, Jack, being played by Andrew's real-life brother Tony.

We didn't see too much of Jack in the later seasons of the show, with him deciding to pursue a career in medicine. So, it remains to be seen whether Jack will be making an appearance in Boston Blue or not.

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As of now, the only Reagans that have been confirmed for Boston Blue are Wahlberg's Danny and Amonsen's Sean, with other cast members including series regulars Maggie Lawson (Psych) as Sarah Silver, Marcus Scribner (Black-ish) as Jonah Silver, Gloria Reuben (The Better Sister) as Mae Silver and Ernie Hudson (Ghostbusters) as Reverend Peters.

We do know that the series will centre on Danny as he reckons with his new job in Boston, where he is set to be paired with Detective Lena Silver (Sonequa Martin-Green), the eldest daughter of a prominent law enforcement family.

Blue Bloods did of course reach its end last year, with the long-running procedural bidding farewell to the beloved cast, which was led by Tom Selleck.

Proving a sad goodbye for many fans, Selleck himself admitted that he was "kind of frustrated" by CBS's decision to end the series.

He said: "My frustration is the show was always taken for granted because it performed from the get-go. So how do I feel? It’s going to take a long time to sort all of this out.

"I remember after the weekend [of the final episode’s shoot], I said, ‘I’ve got to get to bed early tonight because I have to do my dialogue for Monday.’ Well, there was no Monday. It’s just going to take a while."

So, could we be seeing Selleck's Frank perhaps make an appearance in Boston Blue? Never say never, we guess.

Blue Bloods airs on Sky and NOW in the UK. You can also watch it on Paramount Plus – get a seven-day free trial of Paramount Plus on Amazon Prime Video.

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