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.

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.