This Present Darkness by Frank Peretti

For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places.
Ephesians 6:12 (ESV)

Ashton is just a typical small town. But when a skeptical reporter and a prayerful pastor begin to compare notes, they suddenly find themselves fighting a hideous New Age plot to subjugate the townspeople, and eventually the entire human race.

This Present Darkness rivals The Screwtape Letters with its keen insight into spiritual warfare and the necessity of prayer. It is fast-moving, riveting reading, ranking with the best thrillers on the bookshelf. Readers have picked up more than 2.5 million copies since its publication in 1986, and, with its companion volume Piercing the Darkness, it has sparked great interest in spiritual warfare over the years.

"Frank Peretti kicked open the doors that all of us Christian novelists are passing through today. We owe him a huge debt."
Jerry B. Jenkins, Author, The Left Behind Series