Cat and Mouse

by Ralph Williams

"Cat and Mouse" by Ralph Williams is a science fiction novelette published in 1959. When Alaskan trapper Ed Brown discovers a portal to another world, he unwittingly becomes caught in an alien experiment gone wrong. A deadly predator called the Harn has infiltrated the experimental planet, and Ed must face this shape-shifting creature in a desperate battle across two worlds. Armed with limited ammunition and backwoods survival gear, he fights to survive against an intelligent organism that adapts with every attack.