Winton immediately started raising money and organising trains to save the children, and on his return to Britain began finding homes and organising visas for them, all while holding down his day job in London. Word of Winton's audacious plan quickly spread throughout Prague. When he returned to the Czech capital and set up office in his hotel room on Wenceslas Square, long queues soon formed outside of parents who would plead with him to take their children to Britain.

"Those parents were desperate – it was heartbreaking to listen to their stories," Winton, now Sir Nicholas Winton, recalled in a 2007 interview. "They knew all too well what their fate was likely to be. Their first thought was for the little ones. Never themselves. Practically all those parents perished in the camps."

Between March and August 1939, eight Winton trains carried 669 children – most of them Jewish – to safety in Britain. Seventy years on, as the steam train whistled its impending departure, they recalled parents telling them that they were just going on a short holiday, the excitement of the older children and the bewilderment of the younger ones. They remembered their strange first impressions of Britain, spitting out a first sip of milky tea and their wonder at white sliced bread.