David Harewood Teases Role In Supergirl, The Flash Musical Crossover

The Arrowverse continues to be one of the most unique slates on television, with its four live action programs - Arrow, Flash, Legends of Tomorrow, and Supergirl - and growing slate of animated spinoffs dominating much of The CW's output.

One of the most anticipated events of the Arrowverse in the back half of the shows' seasons is the musical crossover episode between Supergirl and The Flash. With the various musical backgrounds of the show's cast, and the recent casting of Darren Criss as the crossover's villain, Music Meister, fans are excited to see the unique crossover comes to fruition.

According to a tweet by Supergirl's Martian Manhunter, David Harewood, it sounds like the Flash episode of the crossover - entitled 'Duet' - is now in the early days of production.

It's about to get pretty busy here. #crossover pic.twitter.com/RcUdQt68cT

— David Harewood (@DavidHarewood) January 27, 2017

The tweet, which shows the front page of the crossover's script, does offer some teases into the technical side of the episode. The script is penned by Aaron Helbing and Todd Helbing, both of whom are executive producers and writers on Flash. And the episode's story comes from the minds of Greg Berlanti and Andrew Kreisberg, who oversee both of the shows.

Although this will be Harewood's inagural appearance on The Flash, it has been reported that he and Supergirl co-star Chris Wood will not be singing in the episode. Instead, those duties will go to Supergirl and Flash stars Melissa Benoist (Kara Danvers/Supergirl), Grant Gustin (Barry Allen/The Flash), Carlos Valdes (Cisco Ramon/Vibe), Jeremy Jordan (Winn Schott), and Jesse L. Martin (Joe West).

In addition, Arrow's John Barrowman (Malcolm Merlyn) and Legends' Victor Garber (Martin Stein), will be performing in the episode.

While details of the musical crossover still remain relatively slim, fans will only have to wait until the two-part crossover premieres on March 20th and 21st.