Anna Hopkins' daily walk through Oxford's picturesque Port Meadow is rudely interrupted one autumn morning when her white German Shepherd, Bonnie, unearths a bloodsoaked body in the undergrowth. For Anna it's a double shock: she'd met the victim previously. Naomi Evans was a professional researcher who had told Anna she was working on a book about a famous Welsh poet, and who offered to help Anna trace Bonnie's original owner. From her conversations...