While conducting volunteer work in Manhattan in 1888, eighteen-year-old Tabitha and Pearl's fates intertwine with Jack the Ripper as he is hunted by the Gorgon Medusa.

It's autumn 1888, and Jack the Ripper is on the run. As London police close in, he flees England for New York City seeking new victims. But a primal force of female vengeance has had enough. With serpents for hair and a fearsome gaze, an awakened Medusa is hunting for one Jack. And other dangers lurk in Manhattan's Bowery. Salvation Army volunteers Tabitha and Pearl discover that a girl they once helped has been forced to work in a local brothel. Tabitha's an upstate city girl with a wry humor and a thirst for adventure, while farmgirl Pearl takes everything with stone-cold seriousness. Their brittle partnership is tested as they team up with an aspiring girl reporter and a handsome Irish bartender to mount a rescue effort, only to find their fates entwine with Medusa's and Jack's.