Vault of the Beast

It came to Earth to find a genius mathematician . . . the one human in the solar system capable of understanding the ultimate prime number. Time is running out. The time-lock on the Beast's millennia-old Martian cage is about to open, and mankind will never be able to deal with the threat!A classic from the Golden Age of science fiction, originally published in the August, 1940 issue of Astounding Science Fiction.