His book Conversations with an Executioner, recounted a series of interviews with Nazi war criminal Jürgen Stroop, a fellow inmate of the UB secret police prison under Stalinism, who was soon to be executed.

It was his idea to rescue, on 11 June 1944, Polish prisoners incarcerated by the Gestapo at Warsaw's Jan Boży Hospital (pl).

[2] Shortly before the Warsaw Uprising by the underground resistance, Moczarski was given a new post as the head of the radio and telegraph services of Home Army's headquarters.

At the same time, he was editor-in-chief of Wiadomości Powstańcze (Uprising News), which was a daily regional addition to the Home Army's Biuletyn Informacyjny (Information Bulletin).

[2] After the collapse of the Warsaw Uprising on 7 October 1944 he left the city with a group of coworkers from BiP along with the evacuees of the Red Cross, and stopped in Pruszków,[2] but returned shortly afterwards, to help with the escape of Jan Stanisław Jankowski, the delegate of Polish Government in exile.

Meanwhile, in place of the AK a new organization was formed by General Anders against the communist takeover, called the Armed Forces Delegation for Poland (Delegatura Sił Zbrojnych na Kraj, DSZ).

Together with Włodzimierz Lechowicz and Zygmunt Kapitaniak, he co-authored a memorandum to his headquarters which stipulated that a new order must be made out to all underground soldiers in the field about laying down arms in the name of reconstruction.

Their proposal was accepted and on 24 July 1945 an order was issued by the Head of DSZ, Colonel Jan Rzepecki, entitled "To former soldiers of Home Army" which stated: On 11 August 1945, five days after the Delegation for Poland officially dissolved, Moczarski was arrested by Ministry of State Security headed by Gen. Romkowski and put on political trial.

Beatings included truncheon blows to bridge of nose, salivary glands, chin, shoulder blades, bare feet and toes (particularly painful), heels (ten blows each foot, several times a day), cigarette burns on lips and eyelids and burning of fingers.

Sleep deprivation, resulting in near-madness – meant standing upright in a narrow cell for seven to nine days with frequent blows to the face – a hallucinatory method called by the interrogators "Zakopane".

[1] Beginning 2 March 1949, as means of psychological torture, Moczarski was locked up for nine months with two German SS-men: SS-Untersturmführer of BdS Krakau Gustav Schielke and SS-Gruppenführer Jürgen Stroop.

[2] During the massive anti-Stalinist upheaval known as the Polish October thaw, Moczarski was retried for the last time, pronounced innocent and released from prison on 24 June 1956.

[3] Other translations include German, published by Droste in 1978; French by Gallimard, in 1979; Hebrew by Loḥame ha-Geṭaʼot, in 1979–80; Czech by Mladá fronta in 1985 (the full version by Jota in 2007); and Ukrainian, by Černìvcì in 2009, among several others.