Safer Than Love — Margery Allingham

Having married a safe, secure headmaster to escape a more dangerous love, Elizabeth lane soon realises she has made a terrible mistake. She plans to leave Victor and get away from Tinworth, a small provincial town where everyone knows everyone else's business. But before she can put her plan into action, she finds her husband dead -- his body is stuffed down a well. And, as if that weren't bad enough, she seems to be the chief suspect in the murder!