[1] The younger Villiers attended high school and graduated from Sciences Po university in Paris.

He had acquaintences among the military and intelligence services who enjoyed helping Villiers describe them and their acts in fiction.

It tells the adventures of the Austrian prince and CIA agent Malko Linge, referred to in the first title as "SAS" (Son Altesse Sérénissime).

This is a play on initials and acronyms: Firstly, Son Altesse sérénissime (SAS) is the French version of "His Serene Highness" (HSH).

Thirdly, the SAS series has always included product (airlines and spirits) placement from varying sponsors over the years.

One of the first sponsors was Scandinavian Airlines (SAS), which flew the hero around in the beginning, although he later set his heart (and the author's wallet) on Air France.

[2] De Villiers' books are well known in French-speaking countries for their in-depth insider knowledge of such subjects as espionage, geopolitics, and terrorist threats, as well as their hard-core sex scenes.

In addition to France, they were translated and popular in Germany, Russia, Turkey, and Japan; and, since some have been published in English since 2014, in the United States and other English-speaking countries.