Recently distracted by the arrival of her and Jamie's second son, Magnus, Isabel Dalhousie - philanthropic editor of the Review of Applied Ethics - is anxious. The next issue of the Review is far from ready, her eldest, Charlie, is jealous, and their housekeeper, Grace, has an officious approach to childcare. With some relief, Isabel returns to helping out at her niece Cat's delicatessen, where surely the most taxing duty is the preparation of sandwiches.

It's not long before Isabel's helpful, philosophical nature draws her into customers' problems, specifically that of ambitious, self-proclaimed matchmaker, Bea Shandon. Bea has staged a potentially dangerous liaison involving enigmatic plastic surgeon, Tony MacUspaig, who may not be quite who he claims to be - and Isabel's help is required in getting to the truth of the matter.

Good-hearted Isabel proceeds with her usual thorough attention to task, and on Bea's advice talks to her friend Rob, a trustworthy regular on Bea's dinner party circuit, and known to have deep suspicions about MacUspaig. It becomes clear, however, that Rob has an agenda of his own and Isabel is now contending with that, along with a mysterious medical condition of Jamie's and some frustrating dead ends when it comes to Bea's predicament.

When the truth finally reveals itself, Isabel must conclude that along with MacUspaig, Bea, Jamie - and even Cat - she herself is not immune to misunderstandings, or the neurotic fantasies that arise from keeping secrets . . .