M-U-S-I-C M-E-I-S-T-E-R! OK OK OK so Let’s hope this cross-over starts a bit more cross-overy than the last one and it’s not a last minute thing. But anyway, let’s react to Supergirl tonight as if we were Sue Sylvester.

Episode synopsis: A new villain comes to National City, putting Supergirl on high alert; at the same time, she faces an attack by the Music Meister. Meanwhile, Winn’s girlfriend, Lyra, gets Winn in trouble with the law; and Maggie attempts to help Winn, but old loyalties get in the way.