The long-running comedy returns to NBC for a 16-episode revival series September 28; Platt will appear on the October 5 episode.
The sitcom is led be a quartet of fellow Broadway alums: Eric McCormack, Debra Messing, Tony nominee Sean Hayes, and Megan Mullally. When it originally aired, the show frequently highlighted stage favorites in guest arcs, including Bernadette Peters as Karen's sister Gin and Patti LuPone as herself.
The revival was also recently renewed for another season.
Prior to Dear Evan Hansen, Platt appeared on Broadway in The Book of Mormon. His screen credits include Pitch Perfect, Ricki and the Flash, and the upcoming comedy Drunk Parents.