The dictionary definition of "ghostwriter" is "one who writes for and gives credit of authorship to another." But "ghost" is "the center of spiritual life; the soul." Is the real soul of a ghostwritten book its ghostwriter?

For most of his writing life, Michael Gruber, 64, wrote speeches for former Environmental Protection Agency head William Ruckelshaus; he "GHOSTED" BOOKS FOR HIS COUSIN, lawyer Robert Tanenbaum. Gruber never got his name on the front of the 15 Tanenbaum legal thrillers. One day it got the better of him, and he began to write his own.

Gruber's first book under his own name was "Tropic of Night." Featuring Miami police detective Jimmy Paz, a character the New York Times called "irresistible," it has been optioned for the movies. The sequel to "Tropic of Night," "Valley of Bones," (Morrow, $24.95) has just been released, and in May, the young-adult novel "The Witch's Boy" will expand Gruber's readership.Gruber's thrillers are creepy and sometimes gory, but they wrestle with issues of spirituality. Gruber is a "practicing Catholic — I'm practicing until I get good at it." He recently talked about how claiming his name as an author revived his writerly soul:

Q: What psychological place do authors have to put themselves in to ghostwrite?

A: At first it was a lark. I considered myself a public servant; I had a kid in college. But I got into it and started developing the characters, and the characters started coming alive.

The Tanenbaum books were domestic comedies wrapped up in a legal-thriller box. They were funny and witty and sad in a way that real novels are, but Tanenbaum was under the impression that people read them because they were interested in the legal issues.

Q: Why don't authors give credit to their ghostwriters?

A: Ego. There are people who are not writers who want to have the glow of being a writer. The power of fiction is such that people reconstruct their own memories in accord with the fiction. When people experience catastrophe, they say "it's just like the movies." That's why people have to read thrillers. You have to secretly write the truth under a tissue of lies.

Q: Both "Tropic of Night" and "Valley of Bones" delve into the paranormal. The paranormal is everywhere right now — books, movies, television. Why is that?

A: G.K. Chesterton said that when people stop believing in God, it's not that they believe in nothing, but that they start believing in everything. As society starts secularizing and formal religion starts losing touch with the divine, superstition starts boiling up.

Q: What's your experience with alternate spiritual worlds?

A.: "Tropic of Night" is based on an experience a friend of mine had. She was a beautiful woman, a white woman, who hooked up with a black nationalist poet. She found herself traveling across the Sahara with this man toward Nigeria. The farther he went, the crazier he became. He started to berate her for everything that had happened in Africa.

She later worked as a medical anthropologist at Jackson Memorial Hospital (in Miami). People would be dying, but there was no physical underpinning for their diseases. These people had been cursed — by voodoo witches, by Santeria. She would go into the community and say, let's do an intervention, maybe get a curandero in.

I tell you in sunny Seattle that weird things happen. Well, weird things do happen. I'm sure they all have scientific explanations, but I don't know what they are.