Jack Randall tries to help a group of "clones" who have been kept in underground caves for their entire lives for the sole purpose of supplying spare parts to their "real-world" selves. This isn't easy due to the complications in Jack's own live which caused him to disappear in the first place, such as the murder of his wife and daughter. Jack must try to save the "Spares" and deal with his past whilst being hunted down by trained killers with a link to "The Gap", one more thing Jack would rather forget. Most of this goes on in New Richmond, a giant broken flying mall which has taken up permanent residence on the ground. A strange place with over a hundred levels, it's a world with a world.