Because he was bored with life on a world that had become a museum, Paul Hilder answered a mysterious advertisement, and found himself plunged into a life that was different, dangerous and far from boring.This is the story of an Earth that existed alongside the one that Paul Hilder knew, and with which he became so involved that the bitter struggle waged on one world threatened to encroach on the other.And it is the story of Ruth, daughter of the powerful Controller Orstey, and her longing for a peace and happiness that did not exist in her own space and time - a peace she tried to find by passing through the cosmic junction of THE ECHOING WORLDS.