Year Zero — Brian Stableford

"It's 1999, and most of the world's computers, according to common belief, are set to regard the coming year as ""Year Zero"" rather than 2000. The Devil certainly appears to think so, and is planning an apocalypse of evil for New Year's Eve. Unfortunately, Molly, who's having a hard enough time just trying to stay clean and get her kids back from Social Services, becomes accidentally entangled in the Devil's scheme. Her potential allies--Elvis, various fallen angels, little gray men, Britain's Men in Black, the masterminds of Peaslee Pharmaceuticals, and ""sanity""--all prove impotent to help her out. It looks as if Molly's going to have to frustrate the Devil's plans all by herself--but it certainly won't be easy A grand science-fantasy adventure"