“The Flash” has a song in its heart and it’s ready to let it out. After way too much anticipation, the musical crossover between “The Flash” and “Supergirl” is here. Surprisingly though, it’s literally nothing like what anyone was expecting.

If you were looking forward to seeing the Flash (Grant Gustin) and Supergirl (Melissa Benoist) speeding around Central City, chirping a tune while fighting a maniacal metahuman, you’re out of luck. Instead, the crossover is going into meta overdrive mode and we’re kind of fascinated by what’s happening.

Figuring it out can be a bit confusing, though. So bear with us while we sort through all of the photos (there are so many), trailers and episode descriptions to break it down for you.

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The musical happens in an alternate reality

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As much as we’d love to see what singing and dancing does to the fight against Savitar, an episode description for “Duet” reveals, “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.”

That gives some perspective to the over-the-top costumes the cast is wearing in photos from the crossover and helps to explain our next point.

The cast isn’t playing their normal characters

You’re not going to see Iris (Candice Patton), Cisco (Carlos Valdes) or even Winn (Jeremy Jordan) singing on the show, it seems. Instead, it will be their musical alter egos. That particular tidbit was divulged by Patton in an interview with Variety.

“You’ll see two versions of Iris in the episode. The Iris that we know and love, and a person they [Barry and Kara] think is Iris but is actually a completely different character named Millie,” she explains. “She’s the sassy daughter of two gangsters — played Victor Garber and Jessie Martin — and she’s madly in love with Mon-El’s character [Chris Wood], whose name is Tommy. They’re fighting for their love, because both of their families do not want them to be together.”

Based on that, it sounds like we won’t be getting the extremely necessary nerd-off between Cisco and Winn. We will, however, get to meet alternate musical versions of quite a few characters, which is exciting. Don’t worry though, Barry and Kara still know who they really are.

Music Meister will first appear on ‘Supergirl’

darren criss supergirl thecw What we know about the Supergirl/The Flash crossover (Its surprisingly quite a bit!)

While the majority of the crossover happens on “The Flash,” it’s all kicking off on “Supergirl” — when Kara is put into a coma by Music Meister (Darren Criss), leading Mon-El and Hank (David Harewood) to bring her to Earth-1 in search of Team Flash’s help. Based on photos from “Supergirl,” it looks like the DEO has Music Meister in custody but it’s unclear how he himself makes the jump to Flash’s Earth.

‘La La Land’ & ‘Crazy Ex-Girlfriend’ writers penned the songs

If you’re going to do a musical episode, you may as well enlist the very best to write the music. That’s exactly what “The Flash” has done. Not only did they look at the home team — bringing “Crazy Ex-Girlfriend” creator Rachel Bloom on board for a song called “Super Friend” that Gustin and Benoist sing — but they also had an eye toward the big screen.

Benj Pasek and Justin Paul, whose music you’ve most recently seen in the critically acclaimed film “La La Land,” contributed the track “Runnin’ Home to You,” performed by Gustin.

There’s also a bunch of cover tunes

While there will be original songs in the episode, keep your ears peeled for some fun covers, as well. As Entertainment Weekly reports the episode will find Benoist singing the old standard “Moon River,” while Jordan, Valdes and guest star John Barrowman perform Jackie DeShannon’s “Put a Little Love in Your Heart.” And naturally, there are a few surprises you’re just going to have to wait to see.


Will the musical stick the landing? Call us crazy but we think it might end up being one of the most fun hours of TV in quite a while. “Supergirl” airs Mondays at 8 p.m. ET/PT on The CW. “The Flash” airs on the same network, Tuesdays at 8 p.m. ET/PT.

Posted by:Chris E. Hayner

Chris E. Hayner is equal parts nerd, crazy person and coffee. He watches too much TV, knows more about pro wrestling than you do and remembers every single show from the TGIF lineup. You may have seen him as a pro-shark protester in "Sharknado 3." His eventual memoir will be called "You're Wrong, Here's Why..." TV words to live by: "I'm a firm believer that sometimes it's right to do the wrong thing."