Strangled in Paris

A "Victor Legris" mystery from Claude Izner, a pseudonym for two sisters who are used book dealers in Paris. Protagonist Victor Legris is also a book seller in late 1800's ("Belle Epoque") Paris, but would rather be solving mysteries, like that of a poor woman, wearing fine clothes and a mask, found strangled on the streets. This book and others by these authors have received very favorable reviews from some trusted sources (Kirkus,  The Historical Novel Society, and Publishers' Weekly who called it Izner's "best yet"), and has numerous elements I like--hints of the occult, murder mysteries, bookstores, historical novels. Nevertheless, after 100 pages, I was not engaged and am getting more hard-nosed about letting things go without finishing them.