When Gestapo agents arrested Irena Sendler on October 21, 1943, they were desperate for information about the Polish resistance network they thought she worked for. But the diminutive social worker whom the Nazis spent (fruitless) months interrogating was no mere foot soldier; rather, she was the bold architect of a smuggling operation that saved 2,500 Jewish children from annihilation, spiriting them out of the Warsaw ghetto via sewers, construction vehicles, "forgotten" crates on city trams…even in toolboxes! In this gripping, harrowing biography, Tilar J. Mazzeo shares Irena's incredible story, along with those of the friends and colleagues who risked everything to help her save the children.