I'd recommend starting with A Scandal in Bohemia. But it might endear him more to the good Mr. Holmes if you pick one where the detective comes out ahead in the end. A Study in Scarlet would be the logical choice, but not if you want him to have enough clues in the narrative to solve the mystery himself. The Copper Beeches, possibly.
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I'd recommend starting with A Scandal in Bohemia. But it might endear him more to the good Mr. Holmes if you pick one where the detective comes out ahead in the end. A Study in Scarlet would be the logical choice, but not if you want him to have enough clues in the narrative to solve the mystery himself. The Copper Beeches, possibly.