Trouble in the Cotswolds (Cotswold Mysteries) by Rebecca Tope

Thea Osborne hopes to spend a quiet Christmas house-sitting for the Shepherds in the picturesque Cotswold village of Stanton, close to Broadway. Walks in the local countryside with the dogs and perhaps a meal in the pub are all the excitement she wants. When her arrival at the village coincides with the funeral of local businessman Douglas Callendar, found electrocuted in his bath, Thea’s interest is stirred but the onset of flu threatens to prevent any sleuthing. However, when two people show up brutally murdered the following afternoon, even battling a fever, Thea finds herself thrust into the middle of yet another police investigation.