Monica Geller and Chandler Bing -- err, the actors who played them -- are back together on the small screen. On Tuesday, Feb. 19, Matthew Perry tweeted a picture from the set of NBC's Go On, where his former Friends wife Courteney Cox is making a guest appearance.

"Courteney Cox is shooting Go On today," the 43-year-old actor tweeted. "She is fantastic, obviously. And my desire to show off in front of her is back in full swing." Cox, 48, retweeted Perry's photo and added that she was "having a blast with Matthew."

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Cox also tweeted a picture with Perry, whom she referred to as her "first box husband." (On her current sitcom Cougar Town, Cox's character Jules Cobb is married to Grayson Ellis, played by Josh Hopkins.)

The former TV couple hasn't appeared onscreen together since Friends' series finale aired in 2004. Cox plays the love interest of Perry's character, Ryan King, in the Go On episode, scheduled to air this April. In the freshman comedy, Perry plays a sports talk radio host who forms unlikely friendships after joining a support group in the wake of his wife's death.

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Cox has worked with a handful of her Friends costars over the years. She appeared on Lisa Kudrow's Showtime series Web Therapy, and the blonde actress returned the favor by appearing on ABC's Cougar Town (the show has since moved to TBS). Cox's BFF Jennifer Aniston has also made cameos on both Cougar Town and the FX drama Dirt.

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Go On -- which also stars Laura Benanti, John Cho, Sarah Baker, Brett Gelman, Suzy Nakamura, Julie White and Tyler James Williams -- airs Tuesdays on NBC at 9 p.m. EST.

This article originally appeared on Courteney Cox and Matthew Perry Reunite on Go On Set