Flash/Supergirl Musical Crossover Features Duet Written by Rachel Bloom, Song From La La Land Duo

The Flash and Supergirl‘s upcoming musical crossover just got even, ahem, crazier.

Rachel Bloom, the co-creator and star of The CW’s Crazy Ex-Girlfriend, has penned an original song for the big event, she tells BuzzFeed. Titled “Superfriends,” the song is a duet — with, I assume, a few meta jokes included for good measure — between stars Melissa Benoist and Grant Gustin.

Additionally, Benj Pasek and Justin Paul, the award-winning songwriting team behind La La Land‘s “City of Stars,” have penned the original song “Runnin’ Home to You,” to be performed by Gustin.

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Explaining the impetus for her own contribution, Bloom said in a statement, “As soon as I heard that they were doing a musical crossover, I e-mailed [CW president] Mark Pedowitz who connected me to Greg [Berlanti] and Andrew [Kreisberg]. I immediately offered them my services. As soon as they picked one of my song ideas, I hopped on the phone with my old Robot Chicken boss Tom Root and … based on that brainstorm, I wrote up the song ‘Superfriends.’ I am so excited to contribute more to the upward trend that is musicals in television and film. Music can be one of the most amazing and efficient forms of storytelling and character development. Also, it was really fun to write a comedy song for two superheroes.”

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Both “Superfriends” and “Runnin’ Home to You” will be performed during the Flash half of the crossover, airing March 21 (8/7c). The crossover begins with Supergirl‘s March 20 episode (8/7c).

As TVLine exclusively reported, Glee‘s Darren Criss will guest-star as the villainous Music Meister. Cast members from both shows — Jesse L. Martin (Joe), Victor Garber (Dr. Stein), John Barrowman (Malcolm Merlyn) and Jeremy Jordan (Winn); and Carlos Valdes (Cisco) — are also scheduled to sing.

How does this latest development make you feel about the crossover? Drop a comment with your thoughts below.

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