Inside the Shadow City — Kirsten Miller

Life will never be the same for Ananka Fishbein after she ventures into an enormous sinkhole near her New York City apartment. Ananka knows she has stumbled upon a big secret, but she has no idea exactly how big. Not only does she discover the Shadow City beneath Manhattan's bustling streets, she meets the mysterious Kiki Strike, a black-clad, Vespa-riding, cafe-au-lait-drinking girl who seems to appear and vanish like magic.

A million rats, delinquent Girl Scouts, and a secret underground labyrinth combine in this remarkable novel about a darker side of New York City you have only just begun to know about .. .