The Beekeeper's Apprentice by Laurie R. King

Sherlock Holmes is retired and studying honey bees in Sussex. He meets Mary Russell, a young American girl, recently orphaned and living with her aunt. He immediately sees in her a kindred spirit with a mind like his own. The novel describes the unfolding of their relationship. Being a big fan of Conan Doyle's Holmes, I was apprehensive about how well King would capture Holmes' voice and if the plotting would disappoint. I needn't have worried. Her Holmes is totally believable. There are several plot lines that unfold to reveal the main story line, Holmes' mentoring of his apprentice. There are several novels in the Mary Russell series and I look forward to reading them.