Rachel Joyce had said that she would not write a sequel to her delightful 2012 novel, "The Unlikely Pilgrimage of Harold Fry," and she has not; this new book is not a sequel, but a companion.

"Harold Fry," an international bestseller and long-listed for the Man Booker Prize, was the moving story of an elderly man who walked the length of England to say goodbye to his dying friend. It was an unexpected delight, a book that could so easily have fallen into twee or sweetness but instead was undergirded with pain, wisdom and humor.

"The Love Song of Miss Queenie Hennessy" covers the same period of time, the same events, but it is told by Queenie, the friend who is lying in her hospice bed awaiting Harold's arrival.

Like "Harold Fry," "Queenie" is delightful and dark. Death, duty and regret shadow nearly every page, but the darkness is not unrelenting; there is humor, and there is light.

For the first 20 or 30 pages, Joyce writes carefully, perhaps overly constrained by the need to parallel the earlier novel. But eventually she relaxes and the book opens up beautifully, painting a remarkable picture of old age from the point of view of someone at the very end of life.

The story is rich in flashbacks, told through a series of letters that Queenie has begun writing to Harold while she waits. It is through these letters that we learn the key to their relationship: Queenie has secretly loved Harold deeply, her whole life, and loves him still. She harbors other secrets, as well as deep regrets, some involving Harold's son, who killed himself.

Rachel Joyce

The act of writing keeps Queenie alive; she needs to tell Harold everything; she needs his forgiveness and absolution. She can't die until he knows it all, and so she lays out her painful secrets like St. Augustine confessing his sins.

The book's humor comes from the unexpected source of St. Bernadine's Hospice, which seems a merry place to end one's days. The nuns are cheery and oddly relaxed; the quirky old residents chat and joke, reminisce, tour the garden, host the occasional drinking party and track Harold's progress through the steady arrival of his postcards.

Still, characters die. Every so often, a patient fails to show up in the day room, and the undertaker's van is spotted outside. Doctors hover over Queenie's bed, speaking ominously: "There is further swelling." "The pain patch was fresh this morning." "Can she take liquid?"

This is a dark book, much darker than "Harold Fry." But Joyce is so deft that when the book is over and you close the cover, the darkness fades. What sticks with you is the light of Queenie's unwavering love.

Laurie Hertzel is the Star Tribune senior ­editor for books. On Twitter: @StribBooks.