Nicholai Hel is an assassin, born in Shanghai in 1925 and raised in a cosmopolitan fashion by his mother, a deposed member of the Russian aristocracy.

The master of this school discovers Nicholai's ability to mentally escape from reality and come back rested and refreshed (mystic transport).

When Japan surrenders in 1945, Hel, after long months of hunger, finds (thanks to his knowledge of many languages) a job as an interpreter in the US Occupation Army and becomes a decoder agent in United States Intelligence.

Using his skills in the art of the "Naked/Kill", a martial discipline that trains in the use of ordinary items as instruments of death, Hel kills the general and is turned over to the American occupation force.

He even develops, in his solitude, a "proximity sense" through which he is aware of any being drawing near (along with its amicable or hostile intentions), and which also allows him to find his way in complete darkness.

The novel begins with Hel who is retired in his late fifties in a small castle overlooking a village of the Haute-Soule, in the mountainous Northern Basque Country.

Having their definitions in the table of contents aids the reader in understanding while Hel and the General are deliberately using these words metaphorically in order to prevent themselves from being understood by other characters.

[6] One year later, in August 2022, it was announced that Chad Stahelski will also direct the project with Matthew Orton being hired to write the screenplay.