In March, Barry Allen (Grant Gustin) made his way to Earth-3 to visit Supergirl (Melissa Benoist), delivering a DC TV crossover fans had been hoping for since the latter hero earned her own series . The Flash's presence on "Supergirl" made for a delightful hour of television which included superhero team-ups against two metahumans, lots of awkward flirting, and a joke about young people on The CW that turned out to come true.

For its second season, producers were quick to confirm that there would be a four-part crossover involving both shows as well as "Arrow" and "DC's Legends of Tomorrow." At the recent Television Critics Association press tour, The CW confirmed that in addition to the four-part crossover, "Supergirl" and "The Flash" will be staging a musical reunion crossover next spring.

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Both casts have rich backgrounds in musical theater, with a number of actors appearing on "Glee," "Smash," and Broadway, and Executive Producer Greg Berlanti said the two-part episode will likely take place during Episode 13 of both shows this coming season and feature two original songs and a mix of covers. "Some of you may know my own personal love of musicals and actors who have been in them," said Berlanti, "and we have a number of people who can sing across all the shows who will be making some very exciting appearances in the back half of the year."

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In the spirit of showcasing the vocal talent of these actors and imagining how these superheroes could find themselves bursting into song, here are 10 musical numbers (in order of likely chronological appearance in the episodes) we would love to see on the forthcoming "The Flash"/"Supergirl" musical crossover.

1. "Dream On" - Aerosmith

While no villain has been announced for the crossover yet, the prevailing theory is that it will be the Music Meister. Since the Music Meister hypnotizes people, singing "Dream On" could be what triggers the dream sequence in everyone in the first place. Another reason why "Dream On" would be a perfect song for the Music Meister to sing is because of the Neil Patrick Harris/"Glee" connection. Harris voiced the Music Meister in the animated series "Batman: The Brave and the Bold" and he sang "Dream On" as a duet with Matthew Morrison on "Glee." While there's nothing official tying Harris to the role in live-action, we're certainly not against it, and the song could be a great way to tie the history the of character together with past versions.

2. "Fight Song" - Rachel Platten

From the beginning of her series, and long before she ever put on a costume and that signature S-shield, Kara's position has always been her ability to fight her own battles and stand on her own. What better song for her to sing in a musical than "Fight Song" by Rachel Platten. This song has become an anthem to women everywhere and encompasses Supergirl's formidable strength. Benoist could sing "Fight Song" during an action sequence or as a reflection of everything she's gone through since she embraced her powers. "Fight Song" could also be a duet between Kara and her sister Alex (Chyler Leigh), as they've both embraced the anthemic lyrics as the superheroes of their own stories. Benoist is an already amazing singer -- she slayed her "Wrecking Ball" performance on "Glee" -- and would absolutely do justice to Platten's "Fight Song."

3. "Cell Block Tango" - "Chicago"

With all of the prisoners being kept in both the pipeline at S.T.A.R. Labs on "The Flash" and the D.E.O. on "Supergirl," it would only be fitting to give them a killer musical number. Imagine the female metahumans from "Supergirl" singing their version of the "Cell Block Tango" from "Chicago." Livewire, Maxima, and Silver Banshee could all sing their stories to the tune of "They had it coming." The song could be re-written to fit each woman's story, including a new way to sing the classic opening of "Pop, six, squish, uh-uh, Cicero, Lipschitz." The choreography could be sharp and sexy and could feature the cell blocks at the D.E.O. Maybe Kara could tour the D.E.O. have to hear all of her greatest villains sing to her as part of Music Meister's dream spell.

4. "Time Warp" - "Rocky Horror Picture Show:

"Time Warp" is a fantastic song for a large group to sing, say, the full casts of both "The Flash" and "Supergirl"... In "Rocky Horror Picture Show" the song is an introduction to the wild world of time travelers and visitors from outer space. That perfectly describes both Barry and Kara. Harrison Wells (Tom Cavanagh) could sing the lead parts, either from the perspective of himself or the Reverse Flash. Cisco (Carlos Valdes) and Caitlin (Danielle Panabaker) could back him up and Barry and Joe could do the tap dancing break in the middle. It could be a wacky group number that Wells and Cisco could pull off with finesse and humor. Everyone could participate, even the audience at home during the "it's just a step to the right" moments. It could explain how Kara and Barry could be in the same dimension as one another if they were part of some interdimensional "Time Warp."

5. "Greased Lightning" - "Grease"

You can't have a musical episode without someone singing something from "Grease," especially since Gustin dreamed of playing the iconic role of Danny Zuko growing up (and previously sang "Summer Nights" on "The Flash"). Considering Barry was struck by lightning, "Greased Lighting" is a must-sing song during the crossover. "Greased Lightning" could be sung in two ways. Either Wally West (Keiynan Lonsdale) could sing it about his new car, or Cisco could sing it about the new Cosmic Treadmill. It would be awesome to hear Wally sing it while showing off his new muscle car to Joe (Jesse L. Martin) and Iris (Candice Patton.) If Cisco sings it, he could dance around the upgraded cosmic treadmill with Dr. Wells and Caitlin looking on in wonder. Better yet, maybe Cisco can build Wally a speedster car! Wally could be given the new car in a dream sequence and then be kidnapped by Music Meister. That would lead perfectly into our next song...

6. "Bring Him Home" - "Les Miserables"

Don't let Jesse L. Martin's roles as a cop on both "Law & Order: Special Victims Unit" and "The Flash" fool you, Joe West needs a solo. With Martin's extensive career on Broadway ("Rent") and his passion for music (having displayed his pipes on everything from "Ally McBeal" to "Smash" to "The Flash" -- at least on Earth-2), the actor deserves to shine in a song that's all his own. While he would sound fantastic singing something classic and upbeat like "Beyond the Sea" or "L.OV.E.", he would also bring so much emotion singing something sad and haunting like "Bring Him Home" from Les Miserables. "Bring Him Home" is the perfect song for a father like Joe to sing. Not only is Joe Iris' father, but last season he discovered he had a son in Wally, and has served as Barry's father since his mother's death and his father's incarceration. Since Joe is the emotional heart of the show, having him sing the song of a desperate father would be heartbreaking. If Joe sang this song about Wally after the Music Meister kidnapping, there would not be a dry eye in the house.

7. "I Need a Hero" - Bonnie Tyler

"I Need a Hero" is a classic 1980s song from the soundtrack to "Footloose." In the film, Kevin Bacon races a tractor to impress a girl. Bonnie Tyler's vocals echo over the heroic moment, and it would be fantastic to hear one of the women of "The Flash" sing it. This song could go to either Iris or Caitlin, or they could sing it as a contemplative duet. These women have both suffered great losses, with Caitlin losing Ronnie Raymond in the wormhole explosion and Iris losing Eddie Thawne to a self-inflicted gunshot wound. Both of these women have experienced heartbreak and this would be a desperate and powerful song for these women to sing as they walk the streets of Central City. Maybe in this moment, as Barry is figuring out how to save Wally, Caitlin and Iris could be joined by all of Central City declaring, "We need a hero."

8. "Man In the Mirror" - Michael Jackson

Gustin has an amazing singing voice and it would be a shame if he didn't get to sing at least one solo in the musical. Assigning a song to Gustin is a difficult talk because Barry is such a complex character. He could sing about his speed, about running, about overcoming -- those would be obvious choices. Giving Barry a ballad, something reflective and personal, seems like the best way to let Gustin's talent shine. "Man in the Mirror" was written by Michael Jackson and is a song about interpersonal reflection. Barry could sing the song alone, while making a decision. Maybe he's questioning his abilities, maybe he's deciding what to do about Iris; maybe he is unsure of what direction take his life in next. "Man in the Mirror" would be a wonderful choice for Barry's solo and will transition perfectly into the next song: his duet with Iris.

9. "I See the Light" - "Tangled"

Over the last two seasons of "The Flash," Barry and Iris have come to see each other as more than just friends. Barry even confessed to Iris that he was in love with her, which she finally said she was open to exploring at the end of Season Two. If the effects of Flashpoint have been reversed by the time of the crossover, having Iris and Barry sing "I See the Light" to each other will be absolutely heart-melting. Essentially the song is about looking on the outside of life, trying to find someone or something else to make you happy. Flynn and Rapunzel sang it to one another in "Tangled" when they realize that what they were looking for was right in front of them the entire time. Considering Barry and Iris grew up in the same house together, realizing that they are meant for each other would be pretty perfect. Patton and Gustin would sing this song beautifully.

10. "Heroes" - David Bowie

We know the perfect final number to close out the crossover's second night. That it would allow the show's producers and performers to pay tribute to the late David Bowie makes it an even better choice. "Heroes" by Bowie is a classic song that embodies the ideals of staying together despite all odds. This song has already appeared in various TV and film musicals including "Moulin Rouge" and "Glee," and it would work as a great finale number for a superhero team-up. It's easy to imagine Barry and Kara getting to walk (or speed) off into the sunset together at the end before heading back to their respective, season-long storylines. If any elements of this episode are dream sequences, maybe Cisco could wake up from the dream at the end listening to this song on his headphones. Cisco is definitely a Bowie fan, right?

"The Flash" and "Supergirl" crossover will air on The CW in Spring 2017.