I mean yes, au fond, it's Judge Dee fanfic, as van Gulik's Dee was Di Gong An fanfic. (And Gulik redrew the Judge to meet modern sensibilities and his own preferences quite as much as Lenormand does.) In a case like this one sees the true accumulative story telling tradition at work. One assumes the anonymous author of Di Goong An was drawing on oral versions but adding his own takes; reinterpreted by van Gulik, reinterpreted by Lenormand. Van Gulik is the better detective writer, for sure; and I'm not competent to judge whether Lenormand's French reads as jauntily as van Gulik's English.
But still--- it's French fanfic. If I want to read French, and I do, I'll read this before anything else I have in the house. (Gide and Sartre and dear god *what* was my mother thinking of? Whatever she was thinking of when she bought Steinbeck and Faulkner, I dare say.) I, umm, think I may order vol 2, if the loonie is as high as it was. And vol 1 goes out to incandescens after my new fridge arrives and I'm free to leave the house.