Praised by Andre Norton, among others, as an "excellent combination of science fiction and fantasy," The Blessing Papers concerns a post-apocalyptic future set in a fictitious Ireland (Imram), in which the ability to read and write has almost been lost and strange images and religions reign. The action and adventure of the three novels dramatizes through many twists and turns the rediscovery through the Blessing family of an almost forgotten past as portrayed in the final recovery of the hidden Blessing Papers themselves.

Turley Vail, with his disturbing visions, is destined to save the world of Imram, but he doesn't want the responsibility. Beneath the scientific wisdom of the Blessing Papers lies a catastrophic evil only he understands. Vanishing deep into the wilds of the island of Imram, he is captured by the Ennis, a primitive people who torture him with their rituals before accepting him. But his survival brings him terrifying doubts: what exactly is the other sinister force that predicts his every move? And how will he safely unlock the precious secret of the Blessing Papers, the sacred prophecies that can bring salvation or doom to Imram?

Turley Vail has succeeded in forming an alliance of the northern Circle Villages of Imram. As the new Center, he has renounced the temptations of the Blessing Papers. But the triumph rings hollow as first his lovely wife Jeneen dies, and then his son Thomas grows distant. But when trouble threatens the Circle people, father and son take off together to the south to root out the cause. Through arid valleys and the forbidding Lower Mountains, their journey becomes a battle for the entire human race, and one man's courage becomes the final test for the future of all things in the rise and fall of the Sigma Curve.