Supergirl and The Flash will be battling the Music Meister in the highly anticipated musical crossover episode later this season.

Executive producer Greg Berlanti revealed the villain during a conversation following the Riverdale panel at the CW's Television Critics Association winter previews on Sunday morning. "We're finishing the script this weekend," he told a small group of reporters, confirming that the team has not yet started casting for the part.

Check out all of TV Guide's Winter TCA coverage here!

Music Meister first appeared in the animated Batman series Batman: The Brave and the Bold, voiced by Neil Patrick Harris. He was bullied as a child for singing in choir, but then discovered he has mind control powers. He sends people to do his bidding after hypnotizing them with his high-pitched singing voice. He developed several music-based weapons and machines based on that power.

In the "Mayhem of the Music Meister" episode of Batman: The Brave and Bold, Music Meister falls for Black Canary until she rejects him due to her feelings for Batman.

Supergirl returns Monday Jan. 23 at 8/7c on the CW. The Flash returns Tuesday, Jan. 24 at 8/7c. The crossover episode hasn't been scheduled yet.

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