Book excerpt: History professor Henry Willows is in love-in love with Catherine Eddowes, the fourth victim of Jack the Ripper. Although over a century distant, Henry's obsession knows no bounds. With the aid of an ingenious physicist, Henry achieves his raison d'�tre: a means to travel back in time, stop the world's most infamous serial killer, and save the woman he loves. But the fabric of time isn't easy to change . . . and the Ripper has plans of his own.