The next crossover for The CW's ever-growing Arrowverse is a musical episode of The Flash that includes appearances by Supergirl's Kara, J'onn, Mon-El, and Winn. The episode, titled 'Duet', is the second Supergirl/Flash-exclusive Arrowverse crossover to date, following last year's episode 'Worlds Finest' - wherein Barry Allen showed up on Kara Danvers' Earth, in order to help the Girl of Steel fight a pair of dangerous rogues.
'Duet' finds Kara and Barry under the spell of the Music Meister, who first appeared in last night's Supergirl episode, 'Star-Crossed'. In Meister's alternate reality, Kara and Barry will be caught up in a musical featuring some of The CW's most accomplished singers. As the final pit stop in the 'Duet' marketing campaign, a new clip has now been released from the episode (ahead of it airing tonight).
While said 'Duet' clip doesn't feature any singing or dancing, the footage does show Team Flash members Vibe and Kid Flash joining forces with Martian Manhunter. Aside from the wonderful looks on everyone's faces when J'onn shows his true form, we also get to see fully-costumed versions of all three heroes prepare to square off against the Music Meister in the world of The Flash.
Considering J'onn sat out the Invasion Arrowverse crossover last year, Wally was sidelined, and Cisco didn't have his costume yet, this is a fun way for all three heroes to get the spotlight. We know eventually our protagonists will triumph against the Music Meister and his schemes, but that won't be the end of their problems.
Over on Supergirl, Kara has to deal with Mon-El's royal past and the Daxamite rulers that are his parents. Of course, that relationship will be strained further as the alternate version of Mon-El inside Music Meister's musical world will be in a relationship with Iris.
The Flash, meanwhile, has a whole lot of time travelers in his future. Not only is Abra Kadabra coming, but a new future guest was just announced. And while Barry won't have to face off against another speedster next year, he still has to contend with who—or what—Savitar is in the present. The musical crossover may provide some reprieve from the drama, but it's just a prelude to the main event coming for both heroes as their series head towards respective end games.
The Flash continues with ‘Duet’ tonight, March 21st on The CW @ 9pm. Supergirl continues next Monday, March 27th with 'Distant Sun' on The CW.
Source: The CW