The Beekeeper's Apprentice: or, On the Segregation of the Queen (Mary Russell and Sherlock Holmes Book 1)

by Laurie R. King

Twice he went to London for week-long training courses, although when he reappeared from the second with a thin cut down the side of his face and a racking cough that lingered for months, I did wonder what kind of training it was. When I asked him he looked embarrassed and refused to tell me. I did not hear the answer for years.

Was this ever brought up again?