This is John W. Campbell's classic science-fiction story about an antarctic research camp that discovers and thaws the ancient, frozen body of a crash-landed alien. The creature revives, returning to life with terrifying results — shape-shifting to assume the exact form of an animal or a man.

Paranoia ensues as the band of frightened researchers work to try to tell friend from enemy, and destroy the menace before it challenges all of humanity!

The story was hailed as "one of the finest science fiction novellas ever written" by the SF Writers of America