Yesterday, The CW confirmed that there will be a two-part musical crossover between The Flash and Supergirl, debuting in the back half of this season. Very little is known about the story, although producer Greg Berlanti teased that they are trying to write one original song for each episode. Most of the songs will be covers of previous hits. Today we have some potentially huge news, with a report claiming that this two-part episode will be directed by none other than Joss Whedon, along with details on the crossover's villain.

The YouTube channel That Hashtag Show has this latest report, which also claims that the villain will be the DC Comics character Music Meister. While we don't know for sure yet if this report is true or not, it would certainly make sense for The CW to bring in Joss Whedon, who has a well-known affinity for musicals. He directed the iconic musical episode of his hit series Buffy the Vampire Slayer, dubbed Once More With Feeling, and he also directed an episode of Glee, the hit musical series which Supergirl star Melissa Benoist and The Flash star Grant Gustin previously appeared on before landing their superhero roles. He also created the cult classic musical Dr. Horrible's Sing-Along Blog.

Of course, Joss Whedon is no stranger to superheroes either, having directed the 2012 blockbuster The Avengers and its 2015 follow-up Avengers: Age of Ultron. The filmmaker famously left Marvel after Age of Ultron, revealing in several interviews how difficult that production was. As far as we know, the filmmaker isn't attached to any upcoming projects, but he revealed after Avengers: Age of Ultron that he wanted to start writing his own original scripts again. We reported a few months ago that he's writing a new script about "a girl who goes though some unbelievable s--t."

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As for the Music Meister, this character first debuted in the animated series Batman: The Brave and the Bold, where he was voiced by Neil Patrick Harris, the star of Joss Whedon's Dr. Horrible's Sing-Along Blog. He also appeared in two issues of The All New Batman: The Brave and the Bold comic books, where he showcases his mind-controlling abilities. He also has a number of musical-based weapons and vehicles, including a car that is shaped as a musical note.

Of course, none of this is confirmed, and since the episode won't air until the back half of this upcoming TV season, it may even be too early to be discussing who might direct these episodes of The Flash and Supergirl. Since Supergirl and The Flash air on Monday and Tuesday nights, they're both positioned perfectly for a two-part crossover, airing on back-to-back nights. Take a look at That Hashtag Show's video below, and stay tuned for more on this crossover.