Danny, a very nice young man if a loner -- he makes this all levitate -- inherits a timebelt and finds that he has a shadow, Don. In fact before long me and my' other self become us (a girl Diane, a baby, even his benefactor) and even if the action is on the slight side, Gerrold hypothecates agreeably with a jump here and a skip there on the nature of existence and destiny. Resilient.