When DEL PIERCE was five years old he was possessed by a demon, and the demon never left. Somehow Del trapped it, locked it away, and managed to grow up almost normally. And now, twenty years later, the demon is breaking out.

Del is far from the only victim of possession. It’s common knowledge in this world that demons have seized men and women throughout history. The 1940’s, however, launched an epidemic of possessions in America that continues to this day. The dozens of new demons echo characters from pulp fiction, golden-age comics, and folklore: THE TRUTH is a Shadow-like figure who executes liars and murderers with his twin .45 automatics; THE CAPTAIN possesses soldiers in combat, making them into real-life Captain Americas; SMOKESTACK JOHNNY is train-riding echo of Casey Jones. Some are harder to pin down, like the LITTLE ANGEL, a curly-haired moppet who brings the kiss of death to the terminally ill. Del’s demon, THE HELLION, is a Dennis-the-Menace-like wild child who plays pranks and can shoot the glasses off your face with his slingshot—a “prank” that cost Del’s mother her eye.

As the novel opens, Del is returning home to Chicago. A demon named THE PAINTER has possessed a man in the middle of the United terminal and is assembling a collage of trash into a realistic picture of a barn and silo and fields—a place that seems vaguely familiar to Del. Del is picked up by his brother LEW and Lew’s wife AMRA. They all have dinner that night with Del and Lew’s mother, in the house where the boys grew up. Del takes Amra to the basement and shows her the comics that Del and Lew created as a kid, the board games they modified. Amra comes upon a slingshot, and Del takes it away from her and puts it away.

Del doesn’t remember how he regained control of his body. His family tried a religious exorcism, and when that didn’t work the family decided to wait the demon out: they tied him to the bed, read him comic books, fed him, and put up with his screams. The demon gradually faded away. There was one relapse when Del was a teenager: he suffered a head injury in a pool accident and the Hellion seemed to awake. Del began seeing a psychologist and eventually learned meditation techniques that kept a lid on the demon. These techniques worked for years, until a car accident sent Del to a hospital where the Hellion stirred again. Over the following weeks, the demon seized control of Del while he slept. Del would wake up to find the room smashed and his neighbors pounding on his apartment door. Meditation had no effect. Del began chaining himself to the bed each night like Lon Chaney.

When the fits continued, Del checked himself into a psychiatric facility, where he became friends with BERTRAM, an intense man who believed Slan-like telepaths secretly controlled the world. Neither Bertram nor Del were helped by the facility’s therapy and drug regimen. With the Hellion growing stronger each night, Del decided he had to find someone else to exorcise the demon before he lost control completely.  

Del tells his family that he’s come back to Chicago to attend the International Conference on Possession, where he hopes to track down a neuroscientist who might have a solution to Del’s problem. Lew drops off Del downtown hotel, where religious protesters are picketing the conference on possession as well as DemoniCon, the parallel “fan” convention. DemoniCon attendees dress up as demons, hold parties and contests, and generally act like science fiction fans. One of the DemoniCon guests of honor is VALIS, a man who claims to be an artificial intelligence that possessed Philip K. Dick when the writer almost died of a heart attack in 1982.

The conference highlights some of the hundreds of competing explanations for possessions. Neurologists categorize them as neurological disorders; epidemiologists look for viruses; religious groups believe that they’re spiritual attacks; Jungian psychiatrists maintain that demons are modern expressions of archetypes from the collective unconscious. Cults, cable TV psychics, and whackos of every flavor attribute possessions to ghosts, telepaths, or aliens. To complicate matters, no one knows how many possessions are faked or misdiagnosed, or how many go undetected. It’s pandemonium.

At the conference, Del sees Dr. Ram talking with O’CONNELL—Mother Mariette O’Connell, an Irish exorcist with a shaved head. Del confronts Dr. Ram and forces his MRIs into his hands. The doctor has discovered which area of the brain is activated during a possession, and Del believes his own MRIs show the same pattern. Del wants Dr. Ram to disable or excise the part of Del’s brain that is hosting the demon—through drugs, radiation, even surgery. An appalled Dr. Ram refuses, saying it’s much to early to try anything that experimental.

A despondent Del gets drunk that night with the circle of fans surrounding Valis. The conversation is geeky: is there a difference between science fiction and fantasy? What if what determines the genre is how the characters react to the world: do they respond as if everything is rational, or do they accept the irrational? Del will keep coming back to these questions throughout the story.

The party is interrupted by THE PIPER, a lewd, pan-like demon, but Del knows instinctively that the demon is a fan imposter, and exposes him. Del isn’t so sure about Valis, though; the so-called A.I. doesn’t seem human, but neither does he seem like the other demons Del’s met. On the way up to his hotel room, the still-drunk Del bumps into someone coming out of Dr. Ram’s room dressed in the trench coat and fedora of the demon called The Truth. The next morning, Del learns that Dr. Ram has been shot and killed.

Del catches Mother Mariette O’Connell as she leaves the hotel. She seems to know his name, and recognizes that he’s been possessed. Del is amazed; no one’s ever been able to sense the demon in him before. O’Connell refuses to help, however. Del decides that she’s the one who can help him, and convinces Lew to drive him to Harmonia Lake, O’Connell’s home in upstate New York.

Harmonia Lake is a Lovecraftian demesne of darkness and fog haunted by the tourist attraction monster called the Shug’arath, or SHUG. At the town’s only motel, Del meets TOBY, the man who has played the Shug for years, a shy, fat giant who tells Del to try the motel’s pancakes. Del tracks down O’Connell and asks her to be her exorcist. She doesn’t believe that Del has trapped a demon, because no one’s every succeeded in doing that. In her experience, there’s no way to kill a demon, and only one way to force it out of a victim’s body—by killing the victim. Del goes back to the motel, and knowing he won’t be able to keep control much longer, contemplates suicide. His plans are interrupted by O’Connell. After more research, O’Connell’s learned that Del’s was the last confirmed sighting of the Hellion. And if Del’s trapped a demon, he’s learned how to do something that could change the world.

That night, a military-style helicopter lands in the motel parking lot, and the Del, Lew, and O’Connell are captured by a group of paramilitary nut-jobs calling themselves THE HUMAN LEAGUE. Bertram, Del’s friend from the psyche ward, has led them here. The league believes A.E. Van Vogt’s novel Slan, about powerful telepaths who secretly rule the world, is the truth masked as fiction, and it’s the league’s goal to take back the Earth for humanity. To Bertram’s shock, however, the leader of the league plans not to enlist Del in their cause, but kill him—reasoning that if Del dies with the demon inside him, they may have finally succeeded in erasing one demon from the world. Before they can execute Del, the Shug attacks. The Shug, it turns out, is more than a tourist gimmick. The demon begins to disposes of the league one by one.

During the struggle, a bound Del is tossed into the lake. In the pool accident and in the car crash, a black well seemed to open up in his vision, sucking him into it, and it happens again now. Before Del had pulled back, but this time he surrenders to it. Del is thinking of his brother, and suddenly he finds himself inhabiting Lew’s body, controlling it. He sends Lew running through the forest, then makes him dive into the lake to retrieve Del’s body. O’Connell is the only one who realizes what’s happened. Del’s body isn’t breathing, and she orders him back into his body.

In the hospital, Del recovers from hypothermia, and Lew recovers from a heart attack—Del had used his brother’s body too roughly. Del is hammered by guilt and confused by his ability to jump like a demon. He leaves the hospital and goes to O’Connell. She agrees to help him, and Del learns why she’s so determined to find a cure for possession: when O’Connell was young, she was possessed multiple times by the Little Angel—the girl who brings death to the old and dying.

O’Connell takes him to New York City to meet with her former therapists and old friends, THE WALDHEIMS. The Waldheims, a couple in their 70’s, are Jungian psychiatrists and possession specialists who believe Carl Jung was directly in touch with the archetypes from the collective unconscious. They offer to hypnotize Del. Later, Del watches the videotape of the hypnosis session. As Del released control, the demon emerged—and it yelled for its “mommy” and fled into a corner. Del realizes what O’Connell had already suspected: Del didn’t trap the demon when he was five—the demon stayed. All this time it was the boy who was trying to escape. Del is the demon.

After a period of shock and confusion, Del decides that he cannot stay in this body. But where can he go? He doesn’t even know how to kill himself anymore. The Waldheims and O’Connell convince him that because he’s a demon, he must know more than he thinks about the nature of demons. In their extensive demonology files, Del discovers that the farm that the Painter was sculpting at the airport keeps reoccurring, and then Del realizes why it’s familiar. The farm scene is identical to one Del drew in the comics he and Lew created as kids. The Painter and Del, and perhaps all the demons, are sharing memories.

Del convinces O’Connell to drive him back to his mother’s house in Chicago. They don’t want to fly, in case they’d be stopped for questioning in Dr. Ram’s murder—Del still feels he might be a prime suspect. He waits until his mother leaves, and then goes in the house—and is surprised to find Bertram living there. Bertram is still feeling intensely guilty about leading the League to Del, and so agrees to keep quiet. In the basement Del retrieves the comic books, and for a reason he can’t explain, his old slingshot as well. He shows O’Connell a spread from RADAR Man #1: sure enough, the picture of the farm is there, and the caption names the place as Olympia, Kansas. They check a map, and discover that Olympia exists. How can they not go?

Halfway to Kansas, they stop at a motel and share a room. They’re both aware of the growing sexual tension, but O’Connell says that she has taken a vow of celibacy. Del awakens later that night with O’Connell atop him, aggressively pinning him, and for a moment he panics, thinking she’s possessed. A moment later he knows he’s wrong, but he also realizes that it was O’Connell he saw coming out of Dr. Ram’s room. She admits that the Truth possessed her, and it was her body that pulled the trigger. When Del confronted the next morning and she recognized his name, she didn’t have any supernatural insight—she knew his name from the MRI reports she’d found in the pockets of the trench coat that morning. Now that Del knows who killed Dr. Ram, he still doesn’t understand why The Truth killed him: for what lie was Dr. Ram being punished?

Del and O’Connell reach Olympia the next day. After a search of the small town, they find a dilapidated farm that Del is sure is the one from the comic and the Painter’s artwork. The farmhouse, which sits across from an old hospital on the hill, is strangely preserved: all the furniture is still there, even though the house looks like it’s been abandoned since the 40’s. They find a child’s bedroom upstairs, and the bookshelves there are filled with stacks of comics, pulp novels, and dime magazines. Del is irrationally certain that this is the place, the source of the demons. The demons are as two-dimensional and mono-focused as these pulp characters, and all they do is act out their stories.

Del is determined to stay in the house that night, and O’Connell reluctantly agrees. Del awakens in the middle of the night, pinned down again, but this time it’s demon Piper—and it’s no imposter. He throws the demon off him. Piper tells him to follow or he’ll miss O’Connell’s big show. The Piper dances into the dark, toward the hospital, where the lit windows of the top floor look down him. Del realizes that the Painter’s drawings were always from the perspective of the hospital, looking down on the farm.

Del runs to the hospital. Inside he sees dozens of demons, and all they’re all acting out their roles: cowboys fighting with Vikings and pirates, the Shug versus the Captain, the Fat Boy raiding the cafeteria.

Del makes his way to the top floor. In the room that overlooks the farm, a very old man sits in the bed, wired to life support machines. The doorway is guarded by a caped figure in red, another superhero. An eight-year-old girl, The Little Angel, sits in the hallway, weeping angrily: the old man in the room is calling to her, she says, but the caped man won’t let her past. O’Connell is unconscious on the floor—Del realizes that she must have come here to try to kill the source of the demons.

At intervals throughout the book, vignettes describe possessions through the years, moving backwards with each chapter: The Captain possessing a soldier in Kashmir in 2004; The Truth breaking into a court trial in 1992 and gunning down O.J. Simpson (for using the now famous “O.J. Defense”—claiming he was possessed at the time of the killings); Smokestack Johnny seizing a train in 1975; and an attack by the KAMIKAZE in 1955 that kills President Eisenhower, brings Nixon to power years early, and triggers Nixon’s “War on Possession,” a war that means two decades of persecution for Japanese-Americans.

The penultimate vignette is from 1944. Billy Noon is the boy from the farmhouse, a twelve-year-old kid with an obsession for comic books and a gift for imagination. He’s leaping from the bridge into the creek with his homemade cape streaming behind him, and his friends are amazed. Billy’s father, a navy sailor, is dead, and Billy fantasizes about his father shooting down kamikaze pilots as they dive for his ship. After his friends leave, Billy slips from the bridge and falls onto the rocks below the water. He can’t move, he can’t breathe. And then he pictures his hero, the Boy Marvel, coming to rescue him. It’s the first of many possessions, and the man in the coma will continue to generate adventures for years to come.

The Little Angel, though, is sure that the old man wants to die now, and she’s determined. She tries to run past the caped man—the Boy Marvel—and he easily grabs her. Del is sure he’s going to kill her. He finds the slingshot in his back pocket and fires, knocking the hero back but not killing him. Del and the Boy Marvel struggle, and during the confusion, the Little Angel climbs atop the old man, and kisses him.

Del expected to die when the source of the demons died, but he remained. All of the demons remained. He helps the bleeding O’Connell out of the hospital and they drive back to Chicago. Del’s memories of being a demon are returning, and he begins to realize a few things. Like why The Truth killed Dr. Ram—Dr. Ram was lying when he said he couldn’t help Del. He also understands something about Valis. At a gas station he calls Valis’ house, but has to leave a message. Hours later O’Connell leaves him at his house with his family. No, not his family, he thinks. Del’s family.

He explains to Del’s mother and Lew about what he’s learned, and what he has to do. This body doesn’t belong to him. As the night progresses, he feels his control slipping. The boy is coming awake. In the middle of the night, Bertram enters his room—but it’s not Bertram, it’s Valis possessing the man. Del says that he saw all the demons at the hospital, except Valis. Valis says he wasn’t invited. So many demons were created by that boy dreamer, but does Del think he’s the only one? Valis was created by a different dreamer. Who knows how many are in the world?

The next morning, Del says goodbye to his family. He tells Lew to hold him down, because last time the boy woke up screaming. He’s sure the boy will recognize Lew, even though he’s so much bigger now.

A final vignette: Months later, the family is celebrating THE BOY’s birthday. There are six candles on the cake. The boy is a five-year-old in a man’s body, and still traumatized. He barely speaks, and has trouble controlling his temper. After an accident with the cake, the boy runs away into the park, where he hides while his family calls for him. A strange man sits on the bench a few feet from the boy’s hiding place and begins to talk with him. The boy recognizes him as the Hellion, and flies into a rage. The Hellion doesn’t try to block the blows, and absorbs them until the boy tires. “I deserve that, and more,” he says. “Though I’ll have to apologize to Bertram.” The Hellion tells the boy that he doesn’t have to worry about being possessed again—he’s under the Hellion’s protection. He also says that he’s working with some people to try to find a way to stop all of the demons. Finally, he leaves a gift for the boy, RADAR Man #1. When Lew finds the boy a few minutes later, he’s reading the comic book. Lew is stunned for a moment, but then he takes the boy’s hand and leads him home.