Wandering City Blues

13 creatures emerged from the ocean, each over 1/4 mile tall. Then came a lethal fog that covered Earth's surface. A small remnant of mankind built cities on the backs of those beasts and migrated up over the fog forever.99 years later, Detective Leon Adler and his mysterious new partner Iris investigate a murder case that takes them halfway around the world to an extinction-level conspiracy. Can they survive the journey, chasing leads on massive skyscraper-perched birds and colonies of inbred cannibals, or will they succumb to the Wandering City Blues?