Synopsis: From the back cover of the News Stand Library first Canadian printing: "Lin Carter, engineer engaged in top secret research at Lockheed, was shaving when the knock came at his apartment door. It could mean an interruption that would make him late for work, he feared - and his fears were realized with a vengeance as a girl so beautiful she was "out of this world" pushed the door open before he could reach it. His apartment door was the first of many doors she was to open for him in the rapid succession of incredible, out-of-this-world adventures that were to take him through the dangers and breathtaking wonders of realms undreamed of by science - yet described with amazing accuracy by works that were supposed to be fiction! Worlds within worlds, through door after door, as his love for this girl drew him on. But the last door of all was already open and through it was coming the living cold of outer space on invisible wings. To close that door, Lin had to close his heart against his love in a solemn pact with a woman of another world who held, for one awful moment, the power to doom all mankind, and bargained with it for Lin's soul."