A mild-mannered literary research assistant comes across previously undiscovered letters from the renowned English poet Randolph Henry Ash which suggest an affair with another poet, Christabel LaMotte. The discovery launches both a modern story of scholarly sleuthing (by the assistant, Roland Michell, and Maud Bailey, a professor at a nearby university and a distant relative of LaMotte) and the circa-1860s romance of Ash and LaMotte. The Victorian story is told via a series of letters and poetry, the evidence that has survived. Byatt’s command of diction in both the historical and modern idioms, and of expression in verse, are impressive. The love affair unfolds as a meeting of sympathetic intellects…