With its fast-paced plots and high-velocity sales, the Left Behind fiction series has popularized pretribulational premillennialism much as Frank Peretti's This Present Darkness interested readers in spiritual warfare in the 1980s. Apollyon, released in early February, is the fifth book in the series, which has sold nearly 3.5 million copies in hardcover and paper editions to become the most successful Christian fiction series in history (CT, Jan. 11, 1999, p. 56). There are also Left Behind themed youth novels, audiotapes, videotapes, clothing, and a popular Web site (www.leftbehind.com), which generates more than 50,000 "hits" a day.

"This is out of our control," says Dan Balow, marketing director for Tyndale House Publishers in Wheaton, Illinois. "We aren't engineering all of this success. It's God really using it in a mighty way."

Series coauthor Tim LaHaye came up with the idea for an end-times novel more than a decade ago. "We are using fiction to teach biblical truth," LaHaye says. His writing partner, Jerry Jenkins, who has authored more than 130 books, brought the project to life. "What we hear from readers is that they have fallen in love with the characters and want to know what happens with them," Jenkins says.

Novels in the series have topped Christian bestseller lists since it began with Left Behind, published in 1995. Now, with new titles appearing about every six months, cash registers are ringing in mainstream stores as well. That excites Tyndale's Balow, who says many readers have written letters stating the books led them to re-evaluate their lives and prepare for the return of Christ. "This is incredibly gratifying to everyone involved," he says.

For LaHaye, who believes the approaching millennium may be ...