Curse of the Ancients (Supergirl, Bk. 2)

National City has recovered from an influx of supercitizens wielding their new powers against each other, and Kara Danvers is hoping for a few weeks of calm in order to focus on her career. She may secretly be a superhero, but she's surrounded by super friends whose achievements are breathtaking.

But when Caesar's Comet comes into view, a powerful curse is unleashed on National City, turning it into Ancient Rome Supergirl and the DEO have five days to figure out who cast the curse and to reverse it. Otherwise, National City may be stuck in the past forever.