The singer-actor and Broadway star becomes the first castmember to write original songs for the Fox musical.

Fox's Glee has set another milestone.

Star Darren Criss has become the first castmember to write (and co-write) original songs specifically for the Fox musical, The Hollywood Reporter has learned.

Criss, who stars as fan favorite Blaine Anderson, wrote original song "This Time," which is set to be one of the last songs Lea Michele's Rachel Berry performs during Glee's two-hour series finale on March 20.

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Criss, who recently signed on to return to Broadway and star in Hedwig and the Angry Inch, also co-wrote "Rise," set to be performed by members of the dramedy's central glee club, the New Directions. Criss teamed with friends Theo Katzman, Sam Hollander, Andrew Thielk, Eddie Montilla and Korey Richmond to write the track — set to be included in the March 6 episode. "Rise" was a song that Criss and company initially created with the goal of having it featured on Glee — they just weren't sure when or where the song would fit in.

That changed when Criss read "The Rise & Fall of Sue Sylvester," when he realized the lyrics and tone of the song fit in not only with the storyline but also with an actual line of dialogue earlier in the episode about "rising from the ashes."

Production on Glee's sixth and final season has already concluded. The series has four more weeks — and five hours — left in its story of the proverbial underdogs. Last week, Criss' Blaine wed on-again, off-again boyfriend Kurt (Chris Colfer) in a dual wedding with fellow fan-favorite couple Santana (Naya Rivera) and Brittany (Heather Morris).

Glee airs Fridays at 9 p.m. on Fox; the two-hour series finale airs on March 20 at 8 p.m.

Email: Lesley.Goldberg@THR.com

Twitter: @Snoodit