The Jewel That Was Ours by Colin Dexter

On an Oxford tour, an American tourist dies suddenly and a priceless Anglo-Saxon jewel destined for the Ashmolean Museum disappears, drawing a sharp-eyed detective and his patient sergeant into a web of alibis, academic rivalries, and quiet deceptions. As they sift through shifting stories from scholars and travelers, they uncover hidden relationships and long-held grudges, leading to another death and a final revelation that ties the theft and murder to a single, meticulous scheme.

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