Very good episode, though it was lacking a lot of Kara, which is odd. The Luthor dynamics are interesting and fun to watch, Brainy and Nia's relationship is adorable, Alex meeting her new (potential) love interest was cute, J'onn struggling with who he is breaks my heart, Kara trying to hide the fact that she's Supergirl from Alex, hell even James having to take a call from his mom, it was a very entertaining episode.
Review of O Brother, Where Art Thou?
