Andrew Terraciano will not return as Sean Reagan in the spinoff, and Mika Amonsen will now take his place in 'Boston Blue'

Mika Amonsen will replace Andrew Terraciano, who played Sean Reagan throughout the 14-season run of "Blue Bloods."Though Donnie Wahlberg is the only member of the core Blue Bloods cast set to return for the long-running series' first spinoff,

The NKOTB residency is on hiatus until November, and Donnie told his Blockhead fans that he started filming Boston Blue on July 7. Then, he shared a behind-the-scenes photo from their table read on his Instagram story, and the photo was a bit on the cryptic side.