A strange and frightening story about an onyx eye and the effect it had on the lives and happiness of several people. It's a well known law of physics that any action has an equal and opposite reaction. You press down on one side of a seesaw, the other side goes up. If you drop a stone into a puddle of water, the water rises an exact proportion to the displacement of the stone. If good luck is on the face of a coin, wouldn't other side bring the reverse? The story begins with Cathy and Jack. He has just presented Cathy with a gift - an onyx eye...