Drifting upstream on the flood-tide in a dank October mist, a loosed dinghy carries the body of a once lovely girl, strangled. No mystery about who she was...everyone in the small Suffolk community devoted to music and sailing knew Hannah, the pleasant, reclusive Czech girl who lived alone in a Martello Tower by a lonely stretch of sand and shingle. The question is: who could have wanted her dead? Chief Superintendent George Gently, now living in the neighbourhood with his new wife, Gabrielle, is busy painting the stairs when the telephone rings: sighing, he agrees to help the local man with the initial stages of the investigation. But in spite of himself he's drawn into the mystery, as they start to question those who might have known Hannah well. Her ex-husband? Her bookshop employer? The local war-hero? The flashy ex-crook who now runs a pub? As the river ripples back and forth in the mellow autumnal sunshine, Gently and the lugubrious Inspector Leyston set about piecing together fragments from the dead girl's life: two dinghies drawn up on the riverbank by the church; a rendezvous note; two cigarette ends; a poem in Czech... it begins to seem that there was more to Hannah than met the eye. And gradually, into Gently's sympathetic and intuitive mind, understanding flows like the rising tide . . .