Even before Supergirl premiered on CBS in the fall of 2015, speculation about whether the series would crossover with The CW's DC Comics television universe had already begun since the series was co-created by Greg Berlanti, who produces Arrow, The Flash, and Legends of Tomorrow. The answer finally arrived when a crossover between The Flash and Supergirl was announced for the tail end of the latter's freshman season. While the crossover episode, 'Worlds Finest', drew some criticism, it was largely well-received by fans of both Supergirl and The CW's DC universe. So, when it was announced Supergirl would be joining The CW, network president Mark Pedowitz was quick to tease even more crossovers.
Though we knew a four-show mega-event crossover was coming, it was also recently announced that another crossover will arrive in the upcoming season between The Flash and Supergirl - this time, with a musical element. Now, we have an idea of who will be directing the episodes and what villain Kara Danvers (Melissa Benoist) and Barry Allen (Grant Gustin) will be facing.
Best known for breaking the casting announcement for Marvel/Netflix's Iron Fist, That Hashtag Show is reporting Joss Whedon will direct the two-part crossover event, with Batman: The Brave and the Bold's Music Meister expected to appear as the villain. Whedon is, of course, who had his hand in multiple well-known geek properties like Buffy the Vampire Slayer and Firefly - the former which featured a fan-favorite musical episode in season 6, 'Once More, With Feeling' - Marvel's The Avengers, and Doctor Horrible's Sing-Along Blog.
Additionally, though no one has been cast as the Music Meister just yet, That Hashtag Show speculates Doctor Horrible star Neil Patrick Harris, who voiced the musically inclined villain on Batman: The Brave and the Bold, may be approached to join The CW's superhero musical crossover. Certainly, given his experience with the character as well as his relationship working with Whedon, it would be logical for the network to at least approach the actor.
Considering Whedon's vast amount of experience working with beloved geek properties - whether through adaptation or creating them himself - it's certain many fans will be excited by the prospect of his involvement with The CW's DC TV universe. Additionally, since he has experience working with musicals both on Buffy and Doctor Horrible, he's uniquely qualified for the job of directing a Flash and Supergirl musical crossover.
That said, it remains to be seen whether the report of Whedon being set as the director for these episodes is confirmed by The CW - or if Music Meister will, in fact, be the villain. Certainly, since the news of the crossover was only recently announced by The CW, it may be some time before the network or any of those involved with the shows offer more concrete information about what fans can expect.
Still, if this video of The Flash stars Jesse L. Martin (Joe West), Carlos Valdes (Cisco Ramon), and Rick Cosnett (Eddie Thawne) singing the theme from Firefly is any indication, the cast may be as excited by the prospect of Whedon directing as the show's viewers:
The Flash season 3 will premiere Tuesday October 4th at 8pm on The CW, Arrow season 5 will premiere in the same timeslot on Wednesday October 5th, Supergirl season 2 on Monday October 10th, and Legends of Tomorrow season 2 on Thursday October 13th.
Source: That Hashtag Show