<Tr> <Td> ← Previous "Into the Speed Force" </Td> <Td> Next → "Abra Kadabra" </Td> </Tr> <Tr> <Td_colspan="2"> List of The Flash episodes </Td> </Tr> <P> "Duet" is the seventeenth episode of the third season of The CW television series The Flash, which aired on March 21, 2017 . The episode was written by Aaron Helbing and Todd Helbing from a story by Greg Berlanti and Andrew Kreisberg, and was directed by Dermott Daniel Downs . The episode features a musical crossover with Supergirl and reunites Grant Gustin and Melissa Benoist with their former Glee co-star Darren Criss, who portrays the Music Meister . Jesse L. Martin also reunites with Jeremy Jordan, with whom he previously worked in the 2012 musical film Joyful Noise . The story begins at the end of the Supergirl episode "Star - Crossed", which aired on March 20, 2017, which saw Kara Danvers / Supergirl (Benoist) hypnotized into a coma by Music Meister, with Mon - El (Chris Wood) and J'onn J'onzz / Martian Manhunter (David Harewood) bringing her to Earth - 1 in hope that Team Flash can save her . </P> <P> J'onn J'onzz and Mon - El of Earth - 38 arrive on Earth - 1 with a comatose Kara Danvers / Supergirl, in hope that Team Flash can revive her . They warn Barry Allen / Flash that the escaped prisoner, Music Meister, claimed he would be coming for him too . Meister appears inside S.T.A.R. Labs and Barry and Wally West / Kid Flash confront him, but Meister attacks and places Barry in a similar coma . </P>

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