When you have written the book that inspired what many people regard as the scariest movie of all time, it's rather hard to repeat that success.
When William Peter Blatty's The Exorcist was adapted for the big screen by Billy Friedkin, the course of the modern horror movie was changed forever.
Here we had a movie that was faithful to the original literary source material and broke every taboo it could.
An adolescent girl's emerging sexuality had never before been properly addressed and in many ways the possessive demon Pazuzu was a metaphor for exactly that.
The great irony of The Exorcist was that so many religious people were disgusted and outraged by it, when in actual fact it was the single greatest endorsement of the Catholic Church in generations.
After all, when you see a pair of priests acting as the only possible barrier between an ancient demon and the soul of a young girl, the Jesuits come out of it looking like heroic warriors.
And now, in his first full novel since The Exorcist was published more than a quarter of a century ago, Blatty once more returns to matters of spirituality and faith.
We begin in Albania in 1973.
Albania, as we now know (because it was an utterly closed society under the Hoxha regime) was a place so stupidly recessive that it made the Soviet Union at that time look like Ibiza on a hen night.
And true to historical form, the novel opens in a dank torture chamber.
"The interrogator sat behind a tight wooden table, with a mind gone blank as the notepad. The prisoner radiated mystery. After seven days of torture, he had yet to utter a word.
"Silent, his head bowed, hands manacled, he stood beneath the blinding grip of the spotlight in the middle of the room like a barrier to comfort."
Who is this mysterious fellow who can endure having all his fingernails ripped out without showing any pain?
In fact, readers of a delicate disposition would do well to steer clear of the graphic torture sequences of the introduction.
However, their interest will certainly be piqued when the prisoner kills his guards and the team of torturers who have been tormenting him, before performing one strange ritual with some Albanian shepherds and then disappearing.
It soon turns out that the nameless chap is actually an American agent called Dimiter and is also known by the nickname "the Agent of Hell" -- and for very good reason. The action then turns to Jerusalem and a hospital that is experiencing some extremely strange phenomena.
A young boy with two separate terminal illnesses suddenly experiences immediate double remission.
Who or what caused this apparently miraculous medical scenario?
Dr Moses Mayo is determined to find a rational explanation for a series of disparate, inherently irrational occurrences occurring in the Jerusalem hospital, but it soon becomes clear that further investigation may not be a very good idea.
Blatty has apparently spent much of the last decade concentrating on The Redemption, and while the prose is sometimes rather clunky, there's no doubting he has, yet again, conjured up a novel that will have people talking -- if only out of a sense of excitement at the publication of a book some see as a follow up to The Exorcist.
It lacks the emotional power of his signature novel, but the sense of ominous mystery that lasts until the final few pages will certainly keep people glued to it.