Time City — built far in the future on a patch of space outside time — holds the formidable task of overseeing history, yet it's starting to decay, crumble .... What does that say for the future of the world ... for the past ... for the present? Two Time City boys, determined to save it all, think they have the answer in Vivian Smith, a young Twenty Century girl whom they pluck from a British train station at the start of World War II. But not only have they broken every rule in the book by traveling back in time — they have the wrong person! Unable to return safely, Vivian's only choice is to help the boys restore Time City or risk being stuck outside time forever...

时间之城--建于遥远的未来，在时间之外的一片空间上--承担着监督历史的艰巨任务，然而它已经开始衰败，崩溃.... 这对世界的未来......对过去......对现在有什么意义？两个决心拯救这一切的时间之城男孩认为他们有了答案，那就是薇薇安-史密斯，一个年轻的二十世纪女孩，他们在二战开始时从英国火车站抢来的。但是，他们不仅打破了书中的每一条规则，回到了过去--他们找错了人！由于无法安全返回，薇薇安无法再回到过去。由于无法安全返回，薇薇安的唯一选择是帮助男孩们恢复时间城，或者冒着被永远困在时间之外的风险......