Elsie Kerr has been beaten badly, raped and left for dead. She begins running a remarkably high fever, and the doctors believe that her condition may be the result of exposure to an as-yet-unknown but particularly virulent strain of bacteria. Considerably out of their depth, leading bacteriologist Sir Marcus Levin is invited to consult on the case and that’s when the real horror begins…

In a moment of consciousness Elsie singles out none other than Sir Marcus himself as her attacker; pointing at him and screaming “Devil Daddy!” before lapsing back into unconsciousness, during which time she inexplicably begins to age at such a rapid rate that a healthy young woman becomes a feeble old crone in a matter of hours.

Sir Marcus is in a quandary. In order to properly investigate this mysterious malady, he needs to be mobile, but there is absolutely no doubt that he has been exposed to whatever it was that took Elsie Kerr! Making matters even more difficult is the fact that Sir Marcus needs to clear his name with the skeptics, who invariably make an appearance after the story breaks on the evening news. Of course, there are no pertinent details of any real use available yet, but rumor and innuendo are more than enough to inflame a mob of fundamentalists already whispering among themselves of witchcraft, alien invasion and the like.

To make matters even worse, Sir Marcus’ close friend, General Charles Kirk of British Intelligence, is unavailable to assist. As it turns out, the horrible truths that are ultimately revealed are far, far worse than the gathering crowd or even Sir Marcus could begin to imagine…