Stephen Lovely must have seen his share of emotional trauma. His new novel, “Irreplaceable” (Voice, $24.95), makes the reader feel grief and longing so tangibly that you wonder what the author has gone through himself.

The novel’s plot is truly unique. Isabel — a happily married plant biologist who lives in Iowa — is killed in a car accident. A chronically ill patient (Janet Corcoran) gets Isabel’s heart, then wants desperately to express her gratitude. She does not let up until Isabel’s mother and husband (Alex Voorman, an archaeologist) come to meet her.

Two fractured families end up forming new and atypical relationships between one another. This alone brings a precious originality to the story.

Lovely certainly keeps you reading, even when you feel you might know how things end. His writing is thoughtful and keeps you plowing ahead to find out what else can come of a widower’s grief and a mother’s desperation.

One weakness, if you can call it that, is Lovely’s development of the heart as a character of its own accord. To the scientifically minded, this part stretched belief a bit. The story gives the heart a metaphysical presence, a link between widower and new owner. Very few people in this world could say whether a transplanted heart holds any more significance than a piece of biological machinery. Lovely’s story says it does.

The reader’s skepticism is lived through Alex, and when he comes around to Lovely’s point of view, I suppose we are expected to do the same.

Lovely’s very real portrayal of grief is nothing to doubt. He gives an utterly convincing portrait of people who have lost the person they love most in the world. It is a touching story.