It was Christmas. Justin stood at the top of his grandparents' stairs and yelled, "Paw-Paw, are you down there?" The basement was dark. Lights flashed and a strange noise rolled up the stairs. Justin moved slowly down the steps and called out again. "Grandpa, where are you?" The lights came on. "What are you doing, Paw-Paw?" Justin stood at the bottom of the stairs. He looked at his grandfather who was kneeling behind a strange looking contraption...