Behind-the-Scenes of “The Flash”/”Supergirl” Musical Crossover

ETonline.com got an exclusive look behind-the-scenes on the set of the musical crossover between “The Flash” and “Supergirl”, chatting with Grant Gustin and Melissa Benoist as they filmed their choreographed superhero musical.

“Well, we’ve gone back in time, as you can see,” Benoist said, gesturing to her glamorous 1920s-inspired costume. “And we’re in this beautiful theater, Barry and Kara are stuck in a dream world and having to figure out shenanigans. They’re on a journey. They’re both on personal journeys sort of figuring things out together as a team.”

The Fastest Man Alive and the Girl of Steel are teaming up for a duet, and to make matters super exciting, the song has a surprising composer. Fellow CW star and Crazy Ex-Girlfriend executive producer Rachel Bloom lent her musical expertise to the project and wrote Kara and Barry’s toe-tappingly fun number, “Superfriends.”

“Obviously, I was excited because I love Grant and he’s such a good dancer and I knew we were gonna have fun, but then when I found out [our duet] was [written by] Rachel Bloom that was even more exciting,” Benoist gushed.

Read more at ETonline.com

Titled “Duet”, this episode of “The Flash” (Season 3, Episode 17) is scheduled to air on The CW in the USA on Tuesday, March 21 at 8.00pm ET/PT.

The Flash — “Duet” — Pictured (L-R): Grant Gustin as Barry Allen, Melissa Benoist as Kara, Carlos Valdes as Cisco Ramon, Darren Criss as Music Meister and John Barrowman as Malcolm Merlyn — Photo: Jack Rowand/The CW — © 2017 The CW Network, LLC. All rights reserved.