The Sentinel, an eight-foot tall, six hundred pound genetically engineered reconnaissance drone is left for dead by an interstellar spacecraft, in the mountains of Colorado. They will not be back. It's alive, and alone, on an alien world. Elizabeth Claywell is a blind, thirteen year old girl on vacation with her family in those same mountains. Elizabeth can sense things the rest of us can't and sometimes it takes a very special turn of events to allow the world to truly understand what it means... To Be Human.