The eleventh Donald Lam and Bertha Cool novel begins with a client who wants the detective agency to undertake a task that he will not stoop to do himself. The client, Harry Sharples, is one of two trustees who administer a trust with two beneficiaries. One of the beneficiaries, Sharples says, is an intelligent, responsible young woman who can be trusted with the money the trustees dole out to her. The other is a young man who is anything but responsible and who will gamble or otherwise fritter away whatever funds he is allowed.
Sharples is worried because a pendant filled with valuable emeralds and which belongs to the young woman, has suddenly appeared on the market. Sharples can't imagine why the woman would be selling the pendant and wonders if she is in some sort of financial difficulty. But he can't bring himself to ask her what's going on and so he wants Lam and Cool to investigate and figure it out for him.
Cool and Lam take the case and Donald begins to investigate. Inevitably, the case will become almost impossibly convoluted, as only a plot by Erle Stanley Gardner can do. A murder will be committed; a pet crow will enter the picture, and Donald will have to fly off to Colombia to check out an emerald mine. None of it makes any sense at all, but it's still always fun to watch Lam in action, bickering with his partner, and conducting the investigation in his own inimitable way. Of course Donald will be a magnet for at least a couple of over-sexed women and all in all, reading the book is a pleasant way to lose two or three hours.