The Evil That Men Do is the third in the Pierre Chambrun series by Hugh Pentecost, which is a pen name for Judson Pentecost Philips, who, per SYKM, won the Grand Master Award from the Mystery Writers of America in 1973. And it’s free right now in the US.
I read most or all of the Pierre Chambrun books many many many years ago, and have fond memories of most, especially of the details of running a big hotel. A couple of them I remember as being a bit far-fetched, but overall I liked them all.
And the title of the first book, The Cannibal Who Overate, which is what got me started on the series, is still on my list of best mystery titles. That list is independent of the quality of the mystery itself – it’s just based on the title. But in this case, I did end up reading and liking that book and the whole series.