“Ka-Tsetnik 135633” is the pseudonym of Yehiel De-Nur (also Dinur; 1909–2001; born Yehiel Feiner, also known as Karl Zetinski), an equally famous and oddly obscure author of Yiddish- and Hebrew-language Holocaust novels. His books have been translated into numerous languages, and much interest has been shown in his literary legacy. And yet he remains, even for his readers, a puzzle.

Undoubtedly the most dramatic moment of the Eichmann trial in Jerusalem was the testimony of Yehiel De-Nur on June 7, 1961, that was abruptly interrupted by the fainting of the witn…