October 1943: The tide of war in the Pacific has begun to turn in favor of the United States and her allies. With the opening of a new offensive campaign, the U.S. military deploys a number of new air groups in the Solomon Islands, including a naval fighting squadron known as the Blue Devils, commanded by Lieutenant Commander Drew McLachlan. From their base at a remote island known only as Conquest, McLachlan and his brave pilots mount a number of successful raids against the enemy, eventually making a name for themselves that comes even to the attention of the Japanese. Soon, however, a new and sinister force begins to stir on the island, seemingly disturbed by the very presence of the American fighting forces. Several men disappear under mysterious circumstances, but their bodies turn up horribly mutilated. The sound of drums begins pounding out of the jungle. And Lieutenant Commander McLachlan witnesses a gigantic, half-invisible shape moving atop the mountain at the center of the island. Soon, the Blue Devils are forced to fight on two fronts: against the known enemy, the Japanese, and an unknown, predatory force on the island that threatens to destroy McLachlan and his men.