One of 12 stories in The Memoirs of Sherlock Holmes, first published in The Strand Magazine and Harper's Weekly in August 1893. Doyle ranked it 18th among his favorite Holmes stories.

Dr. Percy Trevelyan, a young neurologist, seeks Holmes' help. Two years earlier, he agreed to a strange deal with Mr. Blessington, who furnished a house and paid all expenses so Trevelyan could start his practice. Blessington, who has heart trouble, lives there as a permanent patient and takes most of the doctor's earnings. Though Trevelyan has become successful, something about the arrangement worries him, prompting Holmes to investigate.