The European Polygraph 2021/1 published an article on the creator of Polish narcoanalysis entitled “The Use of Narcoanalysis by Polish Counterintelligence in the 1930s”. The biography of Ludwik Krzewiński, and especially his wartime history, deserves a study. An additional point of interest concerns his contacts with the US Military Intelligence Service after 1945 and perhaps also earlier during his stay in the Philippines.