John Stewart Williamson, who wrote as Jack Williamson and sometimes under the pseudonym Will Stewart, was a U.S. writer often referred to as the "Dean of Science Fiction" following the death of Robert A. Heinlein. He won the John W. Campbell Memorial Award for science fiction in 2002.

In Salvage in Space, a spaceman who ekes out a living by mining precious metals from meteors comes across an incredible find - a ship drifting in space with no one aboard. When he gets inside, he finds that there is actually one creature he recognizes alive - a very frightened dog - and one he does not recognize because he cannot see it: an invisible alien that seems to have destroyed and somehow disposed of the entire crew. Now he and the dog must find a way to defeat this indivisible foe or face the same fate.