Metal Snow collects three science-fiction novelettes: Tangible Light (first published in print form in Analog: Science Fiction and Fact), The Oneiric Telefactor (first published in print form in Leading Edge), and Gently Down the Stream (new and never before published). In a different way each story considers what makes us human by showing someone crossing the traditional boundaries of humanity. In Tangible Light, a young man must find out who he is from biographical information about the thousands of people with his exact genetic make-up who have lived before him. The Oneiric Telefactor concerns a man who operates a synthetic body on Venus while sleeping in a lucid dream-state on Earth—except that his body is not on Earth. In Gently Down the Stream, a drug that allows people to control the content and subjective length of their dreams creates the worst addiction-related crime wave in U.S. history. More than five million "zoners" now live their lives almost entirely in a utopian dream, emerging only long enough to get more drug—and doing whatever it takes to get it. To combat this trend, a creative penal system comes up with the idea of curing addicts by replacing their dream worlds with nightmares from which they will be only too glad to awaken.