Inhuman is a novel written by John Russo. It was first published in 1986.
Description[]
At a secluded marriage counseling retreat in the Shenandoah Valley, six couples gather, unaware of the monstrous force about to strike...
Overhead, a jet hijacked by terrorists files toward Cuba...until a desperate plan to stop them backfires. Hideously transformed, their asphyxiated brains shattered, the terrorists escape with only one basic instinct still alive--the ancient bestial need to hunt, to maul, to kill.
Now they are coming, stalking their prey, ready to attack, to crush, to revel in the frenzied spilling of human life. Unarmed and alone, twelve men and women must call on every primitive instinct to survive the killing-lust, the deadly onslaught, the horror that is Inhuman.