United Kingdom, July 18 -- Bridget Moynahan is set to star in the Blue Bloods spin-off series.

The 54-year-old actress has reprised the role of Erin Reagan to star alongside Donnie Wahlberg in Boston Blue.

Donnie, 55, wrote on Instagram: "Reunited and if feels so good! So excited to have my dear friend, and TV sister @bridgetmoynahan, join me for a special guest appearance in the premiere episode of #BostonBlue! She'll also be bringing her incredible directing talents to the show this season! More fun (and surprises) to come. [eyes emojis] Let's go! [heart emojis] (sic)"

The celebrity duo previously played siblings on Blue Bloods, the hit drama series that ran from 2010 until 2024.

And Donnie previously revealed his long-term ambition...