Tom Selleck Welcomes Back Former Magnum P.I. Costar Larry Manetti for Reunion on Blue Bloods

Donnie Wahlberg/Instagram

Tom Selleck is reuniting with an old friend!

The 78-year-old Hollywood veteran — who stars as New York Police Commissioner and family patriarch Frank Reagan on Blue Bloods — will share the screen again with his former Magnum P. I. costar Larry Manetti on an upcoming episode of the beloved CBS family drama series.

Selleck's Blue Bloods costar, Donnie Wahlberg, announced the exciting news in an Instagram post on Monday, where he also shared a group snap of the cast.

"#MagnumMonday!" Wahlberg, 53, wrote. "It's a mini Magnum PI reunion on the set of #BlueBloods this week, with guest star Larry Manetti & Tom Selleck — together again."

"Wishing the late greats Roger E Mosley & John Hillerman could be here, too. 🙏🏼❤️🕊️ #Legends #MagnumPI #BlueBloods #Family," he continued, referencing the show's other two original stars, who died in August 2022 and November 2017, respectively.

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In the sweet pic, the longtime actors are seen smiling together alongside current members of the Blue Bloods cast, including Bridget Moynahan, Andrew Terraciano, Will Estes, and Vanessa Ray.

The upcoming episode will be the first onscreen reunion for the dynamic duo, who starred alongside one another on the CBS popular crime drama that ran for eight seasons from December 1980 to May 1988.

In the crime series, Manetti, 75, starred as Orville "Rick" Wright, while Selleck played the titular role of private investigator Thomas Magnum.

CBS/Getty Larry Manetti (as Orville 'Rick' Wright) and Tom Selleck (as Magnum) in Magnum P.I.

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While the show brought both actors much success, Selleck ultimately left the show to start a quieter life.

"I knew intellectually what it would mean in terms of being a public person, but until you've lived it, there's no way to understand it," he explained to PEOPLE in 2020. "I had a feeling of, 'I don't think I'm cut out for this.'"

Expressing his passion for the show, he continued, "I quit Magnum, not because I didn't like it or I was tired of it. I was tired from it. And I wanted a three-dimensional life because I didn't have one."

Heather Wines/CBS Tom Selleck in Blue Bloods

After returning to acting only a few years later, he's shared that he doesn't believe "there is an endpoint" for his current CBS series, which is currently on its 13th season.

"I think there is a lot of life in the show, as long as you let your characters grow and get older," he expressed while talking to PEOPLE on the eve of the show's tenth season finale.

Continued Selleck: "There is an evolution. It started out as a character-driven show, and it's even more than that now. When you get to a point like this, and we certainly had it on [Magnum P.I.], the audience is really inside the main characters' heads."

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Blue Bloods airs Fridays at 10 p.m. ET on CBS.