Check out Supergirl 4×15 Extended Promo, “O Brother, Where Art Thou?” from The CW. In the episode, Lex Luthor is secretly furloughed from prison. Supergirl 4×15 Extended Promo The series is new Sundays at 8/7c on The CW, and available next day on The CW App. Supergirl 415 Lowdown “O Brother, Where Art Thou?” Jon […]