A Slight Trick Of The Mind:

Mitch Cullin's absorbing "A Slight Trick of the Mind is an original portrait of literature's most beloved detective, Sherlock Holmes, in the twilight of his illustrious life.
Holmes--"a genius in whom scientific curiosity is raised to the status of heroic passion"--is famous for his powers of deduction. His world is made up of hard evidence and uncontestable facts, his observations and conclusions unsullied by personal feelings, until novelist Cullin goes behind the cold, unsentimental surface to reveal for the first time the inner world of an obsessively private man.
It is 1947, and the long-retired Holmes, now 93, lives in a remote Sussex farmhouse, where his memories and intellect begin to go adrift. He lives with a housekeeper and her young son, Roger, whose patient, respectful demeanor stirs paternal affection in Holmes. Holmes has settled into the routine of tending his apiary, writing in journals, and grappling with the diminishing powers of his razor-sharp mind, when Roger comes upon a case hitherto unknown. It is that of a Mrs. Keller, the long-ago object of Holmes's deep--and never acknowledged--infatuation.
As Mitch Cullin weaves together Holmes's hidden past, his poignant struggle to retain mental acuity, and his unlikely relationship with Roger, Holmes is transformed from the machine-like, mythic figure into an ordinary man, confronting and acquiescing to emotions he has resisted his entire life. This subtle and wise work is more than just a reimagining of a classic character. It is a profound meditation on faultiness of memory and how, as we grow older, the way we see the world is inevitably altered.

It is 1947, and the long-retired Sherlock Holmes, now 93, lives in a remote Sussex farmhouse with his housekeeper and her young son. He tends to his bees, writes in his journal, and grapples with the diminishing powers of his mind. But in the twilight of his life, as people continue to look to him for answers, Holmes revisits a case that may provide him with answers of his own to questions he didn't even know he was asking-about life, about love, and about the limits of the mind's ability to know. A novel of exceptional grace and literary sensitivity, "A Slight Trick of the Mind "is a brilliant imagining of our greatest fictional detective and a stunning inquiry into the mysteries of human connection.