The novel explores the concept of a doorway between parallel universes, where individuals can travel to alternate realities. The protagonist discovers this doorway and begins to explore its possibilities, encountering various versions of himself and others in different worlds. As he navigates these alternate realities, he uncovers a complex web of events that threaten the stability of his own universe.
By Keith Laumer · First published 1973 · Genre: Science Fiction, Military Fiction, Thriller