Holmes surprises the audience with the news that this time he will be the narrator and that Watson will be absent from the story.
James Dodd, a veteran of the Boer War, seeks Sherlock’s help, but has trouble starting the interview. After the detective impresses Dodd with his deductive powers, the soldier explains his friend, Godfrey Emsworth, was injured some months previously in South Africa and has since returned to England. Little word has passed between the two, which Dodd thinks is unusual given Godfrey’s friendly nature, but when he visits the family house to make sure things are all right, Godfrey’s uncooperative father tells him not pursue it. As he is leaving, the family butter refers ominously to Godfrey in the past tense, which Dodd infers to mean he has died until the butler bursts out he wishes it was so. Just before he exits, he sees Godfrey looking at him through a window looking deathly pale. Dodd stays one more day and, after discovering Godfrey is being contained in a house in the garden under the watch of an officious looking man, threatens Godfrey’s father with interference until he is satisfied Godfrey is safe.
Sherlock agrees to accompany Dodd to the Godfrey’s family estate at the beginning of next week. The detective brings along an acquaintance of unspecified identity and occupation with them. After asking Dodd to review Godfrey’s physical condition for the sake of the acquaintance, they enter into Godfrey’s family estate. Godfrey’s father threatens them with police action, but Sherlock quiets him down after writing the nature of Godfrey’s condition on a slip of paper and handing it to them, pointing out that police presence will cause what he is trying to prevent by keeping them away. This gains them an interview to Godfrey himself, who seems glad to see Dodd though somewhat wary of a stranger in the person of Holmes.
Godfrey reveals that after getting shot, he was transported to a hospital populated with lepers. He hoped not to contract the illness, but after returning home he perceived its symptoms were beginning to affect him. The family determined to keep things quiet and had him shut into the attached house. Holmes reveals he deduced this from the commonality of the disease in Africa and Godfrey’s pale skin, which is a side effect of treatments of the disease, as well as details such as the butler's gloves being covered in disinfectant. At this point, Sherlock’s acquaintance appears and reveals that Godfrey’s sickness is not leprosy, but a skin condition that resembles it that may yet be cured. The acquaintance (revealed to be a dermatologist) turns to the detective and credits forces beyond human understanding for this happy coincidence.
Unless otherwise noted, all textual references refer to "The Adventure of the Blanched Soldier" from the collection: The Case-Book of Sherlock Holmes by Sir Arthur Conan Doyle.(1)