It didn’t take long after the announcement of a musical Supergirl-Flash crossover for rumor mills to jump the gun with reports of Joss Whedon and Neil Patrick Harris, when in reality producers have only just begun assembling the four-way crossover. Now, DC boss Greg Berlanti updates on the musical, including a writer “we’re really excited about.”

The same IndieWire interview that saw Berlanti clarifying Supergirl’s role in the four-way crossover also brought word of early progress for the musical, currently eyed as a two-part crossover at some point in the latter half of either season. This fall’s crossover remains the priority, but they’ve at least begun the process of gathering and writing songs:

We just finished writing the fall crossovers. And now we’re trying to figure out how to produce them. That’s probably the most challenging thing we do all year. And now we’re doing it across three shows! But next week we’ll have to start talking about clearing music. I have a few ideas for tone and style in my head but we’re just starting to talk about what that can be. I do want to try and get an original piece of music written. As we make a deal on that we’ll probably make some announcements on the original songs.

Berlanti wasn’t asked about the Joss Whedon rumor, though when the interview posed Lin-Manuel Miranda as an option, Berlanti hinted at perhaps some recognizable talent involved:

[laughs] I would say, pretty close. I can’t say yet because we don’t have a deal yet, but I did speak to someone we’re really excited about. There are some writers I’m incredibly excited to work with.

It’s doubtful any significant updates will arrive for another few months, but who might Berlanti have in mind to help steer Flash and Supergirl through a musical, if not Joss Whedon or Lin-Manuel Miranda?

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