As the editor of an applied ethics journal, Isabel Dalhousie is usually tucked away in her editorial office, in the comfortable Edinburgh house she shares with her fianc and their young son, and does not often meet many fellow philosophers. But while helping in the delicatessen owned by her niece, Cat, she meets Jane Cooper, an Australian philosopher who is spending a sabbatical in Scotland. Isabel learns that Jane needs to find out something about her past. Jane was born in Scotland but taken to Australia as a baby by her adoptive parents. She knows who her mother is, but her father's identity is still a mystery. Can Isabel help Jane unconver this important and potentially unsettling information? And in Isabel's own life, there is the ever-present question of marriage, and also the perennially difficult issue of her relationship with Cat, whose choice of men is as dubious as ever.