Martha Grey, having escaped the hard work of being a companion and nurse to the late Marcia Gilbert, and narrowly missing the dubious honour of becoming Mr. Greening's wife, leaves Seacliffe. Heading home to her now unencumbered property in Stretton Wakefield, she detours, as a final duty to her deceased employer, to deliver pets and bequests to Marcia's niece, Miss Frances Gilbert. On the journey to the beautiful but run-down estate of Cobbleigh, where Frances lives, Martha becomes unwell and on arrival, faints. Frances, and her staff at Cobbleigh, mistake Martha for Marcia and Frances pleads with 'her Aunt' to help rescue the estate from ruin. What should Martha do? Will she be able to help? And what will be the outcome of Changing Places?