Recommended reading - The Exorcist (1971) and Legion (1983):

The Exorcist

By William Peter Blatty.

Published by Harper Paperbacks.

First published in 1971.

Paperback.

ISBN-10: 006209436X

ISBN-13: 978-0062094360

Description:

Four decades after it first shook the nation, then the world, William Peter Blatty’s thrilling masterwork of faith and demonic possession returns in an even more powerful form. Raw and profane, shocking and blood-chilling, it remains a modern parable of good and evil and perhaps the most terrifying novel ever written.

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Legion

By William Peter Blatty.

Published by Tor Books.

First published in 1983.

Paperback.

ISBN-10: 0765327139

ISBN-13: 978-0765327130

Description:

“Jesus asked the man his name, and he answered, ‘Legion, for we are many.’” – Mark 5:9.

A young boy is found horribly murdered in a mock crucifixion. Is the murderer the elderly woman who witnessed the crime? A neurologist who can no longer bear the pain life inflicts on its victims? A psychiatrist with a macabre sense of humor and a guilty secret? A mysterious mental patient, locked in silent isolation?

Lieutenant Kinderman follows a bewildering trail that links all these people, confronting new enigmas at every turn, even as more murders occur. Why does each victim suffer the same dreadful mutilations? Why are two priests among the dead? Is there a connection between these crimes and another series of murders that took place twelve years ago – one that supposedly ended with the death of the killer?

Legion is a novel of breathtaking energy and suspense. But more than this, it is an extraordinary journey into the uncharted depths of the human mind and the most agonizing questions of the human condition.

The answers are revealed in a climax so stunning that it could only have been written by the author of The Exorcist – William Peter Blatty.