The Flash 3x17 Promo “Duet“ (HD) Season 3 Episode 17 Promo - Musical Crossover with Supergirl

The Flash 3x17 “Duet“ Season 3 Episode 17 Promo - DARREN CRISS (“GLEE”) GUEST STARS AS THE MUSIC MEISTER IN THE FLASH AND SUPERGIRL MUSICAL CRO...