This is the first-hand account of a soldier from the SS, who, after the order to surrender, escaped and, after adventures, enlisted as a mercenary in the Foreign Legion.

Having been sent to Indochina to fight the Viet Minh, the "German Battalion of the Damned" implemented: Bomb to bomb! Bullet to bullet! Murder to murder! "The Devil's Guard" is the personal document of reprisals and counter-reprisals of a man and his unit, a record of criminal violence from both sides, of a war in its rawest, wildest, and most chilling form.

The book was first published in English in the 1970s, causing stormy reactions and disagreements from critics and the reading public. It sold out in a short period and remained for decades a ghost book, with no one able to find a copy except in specialized antiquarian bookstores and at very high prices.

Today, it is perhaps rightly considered by experts and ordinary readers to be the most representative book ever written about World War II and the French Foreign Legion.