Rudolf Hoss was the kommandant at Auschwitz, the byword of the World War ll Holocaust, the concentration camp of the deaths of 1.3 million people, 90 per cent of which were Jews.

Hoss was the first high profile Nazis to admit to the extent of wartime Germany murders, which drip fed to admissions during the trials at Nuremburg. Here arrested Nazis leaders confessed to 'following orders”.

But for the pursuit by one man, Hanns Alexander, a German Jew now a captain in the British Army, the Hoss story may not have emerged so soon after the end of hostilities.

The story of Hoss and Alexander, an uncle of the author Thomas Harding, is told in parallel chapters – The Good and The Ugly, if you like.

The effect is that of a novel. Each page adheres the reader, each page exhaustingly researched and fact upon unalloyed fact renders us unsettled.

Hoss went to the gallows after the war; Alexander died in 2006 a retired banker in London. Despite the author's family ties,

Harding delves behind his uncle's serene, jovial peacetime demeanour to uncover an zealous interrogator, at one point hinting at violence, or turning a blind eye towards violence perpetrated by Hoss' captors, which comes across as one of Herge's Adventures of Tintin.

Hanns has been portrayed as the war's first Nazi hunter, not an unreasonable conclusion.

Harding's research took him to the United States, where he interviewed wartime prosecutors; he moved quickly as time was running out.

He had only found out on his uncle's death that Hanns had captured, in person, the kommandant of Auschwitz.

Otherwise, it had been kept a family secret. Hanns and Rudolf – the German Jew and the Hunt for the Kommandant of Auschwitz published by Heinemann is an arresting read. Uncovered are many elements of Nazis atrocities.

Hoss was two removes from Hitler – he answered to Heinrich Himmler – and the reader is immersed in reality. We read once again of Holocaust atrocities. And we remain bilious.

– Phil Campbell, QSM.