Of the ever-blooming crop of debut authors, John Twelve Hawks styles himself as the most mysterious: Apparently, he lives somewhere ”off the grid,” never to be photographed or interviewed or identified by his real name (according, naturally, to his publicist). The self-mythology would work better if he had written a less disappointing pulp sci-fi page-turner. His novel, The Traveler, is initially a propulsive and ambitious goof about sword-toting warrior woman Maya (Beatrix Kiddo mixed with the Terminator) protecting a ”Traveler” — that is, one of those who ”can project their energy out of their bodies and cross over into other realms” and are ”the only real force of change in the world” — from destroyer forces called the Tabula. Yet the book’s leaden, repetitive ridiculousness soon becomes irksome, especially the incessant and self-serving insistence that any of us living ”on the grid” — everyone except the author and his imaginary friends, basically — is a mindless sheep. Perhaps we should flock to a worthier book this summer.