Shadow Twin is a 120 page novella by Gardner Dozois, George R.R. Martin, and Daniel Abraham. Gardner began the novella in the 1970s, handed it off to George in the 1980s, who, in turn, called upon hot new writer Daniel Abraham to add the finishing touches.

Includes an afterword by all three authors, illustrated with a full-color dust jacket and black and white full-page illustrations by Michael Kolesch.