IN HUMAN FORM—THEY WERE CONTAGION TO HUMANITY! To the naked eye the girl now entering her house looked like a normal human being. Cautiously Wade Harper moved out of his hiding place into her view. Could this attractive young lady possibly be his quarry? With his unique mental talent, he threw a thought probe at her. What happened then was so shocking that instinctively he drew his gun and fired at her. For in her first unguarded thought she had revealed herself. She had called him a Terrestrial bastard! Thus began the horror that threatened to turn the human race into the walking dead!