At St. Benet's-by-the-Wall, a small church in the City of London, Nicholas Darrow heads a ministry of healing. He is a clergyman in his mid-forties, blessed - and cursed - with both true healing powers and a deeply mysterious allure. After a tempestuous youth and a rocky entry into the priesthood, he has settled into an outwardly satisfying routine: weekdays at the church, weekends at home in the country with his wife and two young sons.

But he is haunted by a profound and dangerous weakness: at times of greatest stress, he falls into the habits of a "wonder worker," believing his powers to be God-like rather than God-given. And recent events at St. Benet's - a "demonic brew" of obsession, deception and desire - are beginning to push him in that direction.

The arrival at the Rectory of a new live-in cook - a gentle, shy, emotionally needy woman in her early thirties - seems to precipitate a severe spin out of control at St. Benet's. But the "arrogance, obstinacy and . . . glamorous detachment" that have begun to rule Nicholas now put him at the center of the downward spiral.

His powers suddenly dazzling and infinitely dangerous, he must undertake an arduous struggle to regain emotional and psychic equilibrium or risk ruining, in the most insidious ways, every life he attempts to heal.