After 1940, survival in Nazi-occupied Paris often came down to paper. A stamp. A signature. A word printed in ink. For Jewish families, that ink could decide everything. Adolfo Kaminsky was still a teenager when he realised this. He was not armed. He had no rank. What he had was chemistry. From a small workshop and later from hidden rooms across Paris, he learned how to erase danger without tearing the page. One document at a time, he quietly helped thousands of people slip past a system built to destroy them. A chemistry skill learned by accident Adolfo Kaminsky was...