Barry and Kara get their glee on in this sneak peek of the highly anticipated THE FLASH/SUPERGIRL crossover episode titled “Duet.”

How to make a musical episode legit in an action-adventure series with superheroes? Well, just create an alternate reality and go from there. That’s what’s the case with this gleeful The Flash/Supergirl crossover “Duet” episode. Alas, you likely will not be seeing this with a The Flash and Arrow crossover, but anyone willing to show off their musical talents are bound to make a way.

As such with Grant Gustin and Melissa Benoist, who’ve both had their time in the music-filled series, Glee. Enter in a guest appearance by another Glee alum, in this case Darren Criss, and you’ve got yourself a musical reunion. Add in some co-stars that were already highly musically adept, and you’ve got yourself a grand ole’ time.

Watch two more sneak peeks below!

Barry (Grant Gustin) and team are surprised when Mon-El (guest star Chris Wood) and Hank Henshaw (guest star David Harewood) arrive on their Earth carrying a comatose Supergirl (guest star Melissa Benoist) who was whammied by the Music Meister (guest star Darren Criss). Unable to wake her up, they turn to Team Flash to save her. However, the Music Meister surprises The Flash and puts him in a similar coma, one that Team Flash can’t cure. Kara and Barry wake up without their powers in an alternate reality where life is like a musical and the only way to escape is by following the script, complete with singing and dancing, to the end.

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