Boston Blue star Donnie Wahlberg has explained why the majority of filming for the Blue Bloods spin-off took place in Toronto rather than Boston.

The show follows Sean Reagan (played by Mika Amonsen) as he begins his career as a patrol officer for the Boston Police Department, with his father Danny Reagan (Donnie Wahlberg) joining as a detective.

However, Boston is a long way from New York and the rest of the Reagan family, so Danny will have to put in extra effort to work well with sharp and fearless Detective Lena Silver (Sonequa Martin-Green).

While the title confirms that Boston Blue is set in Boston, only some of the exterior scenes were actually filmed in the famous city.

Most of the shooting, which took place over the summer, was done on a soundstage in Toronto, Canada, leading to some negative feedback from fans ahead of its debut.

Actor Donnie Wahlberg reprises his Blue Bloods role of Danny Reagan for the spin-off Boston Blue. (Image: CBS)

CBS’ Boston Blue premieres on Friday, October 17. (Image: CBS)

Wahlberg addressed this issue during an appearance on the Billy and Lisa in the Morning podcast, explaining that financial constraints prevented more filming from taking place in Boston.

He recalled: “When I initially was offered the job, I said, ‘We got to go to Boston.’ They said, ‘We can’t afford it.’”

Despite this news, the 56-year-old didn’t take this news lying down as he went on to clarify: “It’s basically thirty cents on a dollar to film in Canada right now, compared to eighty cents on a dollar, ninety cents from a dollar even with tax breaks.

“But I said, ‘We have to go to Boston. I can’t not go to Boston.’

“And so the plan right now is to do the interiors up here [in Toronto] and go to Boston every couple of weeks and do what we did and put a crew together, a Boston crew, and go down and film all over the city.”

Boston Blue’s Detective Lena Silver is played by actress Sonequa Martin-Green. (Image: CBS)

Wahlberg continued: “You can’t fake what Boston looks like. And you know, we’re bringing Boston actors up here to guest [star] in the show.

“We’re doing everything we can, and hopefully, in success, we can be in Boston more.

“The goal is, let’s compromise to get the show made. We’ll work outside and do exteriors in Boston, and then you know, in success, perhaps we can come down there and be there full time.

“That would be a dream of all dreams.”

Several iconic Boston landmarks have already been confirmed for the series though, much to fans’ delight, including Fenway Park, Granary Burying Ground and various other locations around downtown Boston.