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　　Hannah Fry uncovers the secrets behind the miraculous technologies of the modern world,revealing the mind blowing stories behind their invention. 　　Episode 1: Passport 　　Hannah gains access to a top-secret site where anonymous staff and the latest tech work to make the British passport one of the most secure documents on the planet. 　　Episode 2: Vacuum Cleaner 　　Hannah Fry reveals the ... (展开全部)