he is the son of jozef kropinski, perhaps the most prolific and versatile composer in the entire camprancesco lotoro brought it to light. >> waldemar kropinski ( translated ): i thought it was something that was of no interest to anyone because my father was already dead and not even one camp composition of his was performed in poland. >> wertheim: jozef kropinski, a roman catholic, was 26 when he was caught working for the polish resistance and sent to auschwitz, where he became first violinist in the men's orchestra and started secretly composing, first for himself, and then for other prisoners. ♪ ♪ in 1942, he wrote this piece that he titled "resignation." ♪ ♪ >> kropinski ( translated ): this is the list my father did seven months before his death. >> wertheim: oh, this was all of his music. kropinski wrote hundreds of pieces of music during his four years of imprisonment- at auschwitz and later at buchenwald-- including tangos, waltzes, love songs, even an opera in two parts. still more astonishing, he composed most of them at night, by candlelight, in this tiny room- the nazis d