Bill Bergson and the White Rose Rescue (original Swedish title Kalle Blomkvist och Rasmus) is the 3rd and last novel about the Swedish "master detective" Kalle Blomkvist, written by Astrid Lindgren. It was published in 1953, during the Cold War. The professor's invention of impervious light metal is significant to the war industry and the kidnappers' motive is not financial, it's political. Nicke, a kidnapper, says that he "could do what else for the thing and everything was right which could promote the thing" ("kunde göra vad som helst för saken och allt var rätt som kunde främja saken"), but the engineer Peters threatened him: "Jag behöver väl inte påminna dej om hur det går för såna som försöker hoppa av?" ("I don't need to tell you how it goes for people who tries to defect?").