This urban fantasy was originally released in 2004. World-Walkers are able to use Gatestones to travel between alternate reality worlds. Central, the guiding organization behind the Walkers, tasks them with keeping the worlds separate and to prevent unauthorized walking which Central feels will result in chaos and destruction. A group of others, known as New Worlders, think the opposite is true: that the worlds must be kept connected to keep all of them viable. Suli Grail is World-Walker. She is assigned to track, stop, or kill the Other, a natural Walker who doesn't require a stone to walk between Worlds. The Other is jumping worlds that contain his dopplegangers, known as Jesse Farrell. All are musicians and all share an abusive childhood. Some have dealt with it better than others, and the Other is trying to find and reconcile his past by becoming one of the Jesse's. Complicating Suli's pursuit of the Other is their past relationship- one she's not sure she wants to destroy.

This is a bit of a complicated story. There are time and space jumps between worlds, at least three Jesse Farrells to deal with, and a complex, twisting plot that crosses and recrosses the lives of the characters. Those characters are interesting and complicated and very human. The story is mostly told from the viewpoint of Suli Grail, the World-Walker, and the Jesse Farrell that is the object of the Other's pursuit. Jesse is confused and off-balance at first, knowing but not quite understanding what is happening. His viewpoint is done quite well and left me feeling lost and confused for a good portion of the story. But it was lost and confused in a good way because it made Jesse's search for answers compelling and pulls you into the story, wanting to know what's going to happen. Suli's part is the grounding. It's where we learn the mechanics of world-walking and much of the background of the main story.

Stories that involve time and reality travels can be hard to keep straight, but the time jumps that criss-cross past and present here are handled well and don't get so complicated they become all wibbly-wobbly. Secondary characters are nicely written and a few stand out as memorable, notably Dr. Zelig and Ariel.

This is a nice alternate reality urban fantasy that fans of time travel, modern day fantasy settings, and alternate reality tales would enjoy.