In 1980, Dean Koontz was hired to write a novelization of The Funhouse. At the time, he was not yet a household name. He still regularly worked as an author-for-hire under a string of pseudonyms; for this book, he originally published as Owen West. While Tobe Hooper was in pre-production, Koontz was assigned to turn Larry Block’s screenplay into a fast, accessible novel. He was not particularly impressed by Block’s story, but he liked the idea of writing about a carnival. Production delays meant the novelization reached stores in late 1980, months before the film. It sold well at first. When the movie finally opened in 1981 and did disappointing business, the book’s sales collapsed. Years later, after Koontz had become a bestselling author in his own right, The Funhouse was reissued under his real name.

The first thing that stands out is how little the novel has in common with Hooper’s film. The movie, of which I am a fan, is a fairly straightforward, atmosphere-heavy slasher. Teenager Amy and her three friends hide in the funhouse after the carnival closes, witness a murder, and find themselves hunted by a carny and his son. Those elements are all present in Koontz’s book, but he adds a large amount of backstory, most of it centered on Amy’s alcoholic mother, Ellen.

In the novel, Ellen is the ex-wife of Conrad the carny. A runaway, she married him without realizing he was a Satanist who hoped she would give birth to the Antichrist. When their demonic infant attacked her, Ellen crushed the baby. Conrad swore revenge: he would let her go so he could hunt her down later and destroy whatever family she built. What plays as random bad luck in the film becomes something very different here. Over the years, Conrad and his second son, the deformed Gunther, take their carnival from town to town in search of Ellen and her new family. The other carnival workers are drawn as sympathetic figures, people on the margins who have formed a family of their own and have no idea how depraved Conrad and Gunther really are.

Family is the novel’s real subject. Ellen has remarried and has two children, Amy and Joey. In the film, Amy is a typically naïve final girl, and Joey is an annoying brat who sneaks out to the carnival. Ellen appears only briefly and makes little impression, though she is seen drinking as Amy leaves the house. In the book, Ellen hits Amy when her daughter says she is pregnant, then pays for the abortion because she fears Amy might give birth to the Antichrist. Joey is terrified of Ellen and runs away to the carnival because, like Ellen before him, he wants an escape from a dysfunctional home. The contrast between the carnies’ supportive found family and Amy and Joey’s abusive “respectable” household is easy to spot, but it still works.

Koontz’s eye for detail and his gift for vivid characterization lift The Funhouse above the usual horror novelization. The plot is occasionally stretched thin. Conrad’s revenge scheme never quite makes sense.  What if Ellen had stayed unmarried and never had another child? Even so, Koontz keeps the action moving and is smart enough to lean into the melodrama without apology. He even lands a surprisingly moving final scene.

This is a case of a novelization that diverges sharply from its source. I like both Hooper’s film and Koontz’s novel. They are both wonderfully macabre. The film is true to Hooper’s aesthetic. The novel is pure Koontz.