The reality of production constraints leave Flash and Supergirl only enough time for a few original songs in their musical crossover “Duet,” but that doesn’t mean additional voices won’t fill the air. Find out what other big numbers will get Barry and Kara tapping their feet, as well when we might expect another Arrow-verse musical extravaganza.

An Entertainment Weekly in-depth look at the March 21 (technically kicking off March 20) musical event revealed additional musical numbers beyond the Rachel Bloom-written “Super Friend,” and La La Land duo Benj Pasek and Justin Paul’s “Runnin’ Home to You.” That’s likely all we can expect from original tunes, but see what else made the cut:

The episode also includes several covers, among them the [Melissa Benoist] solo “Moon River,” and an ensemble performance of Jackie DeShannon’s “Put a Little Love in Your Heart” that brings the denizens of the ’40s nightclub to their feet as the [Music Meister] conducts [Jeremy Jordan, Carlos Valdes] and John Barrowman in an epic, upbeat dance number choreographed by Glee’s Zachary Woodlee.

The report also notes that the musical-within-a-dream approach will see Jesse L. Martin, Victor Garber, and John Barrowman as rival mob bosses, while Jeremy Jordan plays club pianist to Carlos Valdes’ aspiring artist busboy. Not only that, but executive producer Andrew Kresiberg is already thinking about a potential successor to their first musical crossover, wherein Darren Criss might get to utilize some of his own songwriting talents:

Should the crossover prove successful, Kreisberg even has hopes for a sequel, and Criss would be elated to return to the wild, wild world of singing superheroes. “I would have liked to have written some songs,” quips the actor and musician, who landed the role too late in the process to do so. “I want to come back, I’m not done — then I’ll have my true payback!” Watch out, Flash!

The two-night event will get started with Supergirl on March 20, and crescendo in the following night’s Flash “Duet.” You can check out the first photos and footage below, and stay tuned for more.

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