One day, nobody dies. All across the world, nobody dies. And then the next day, and the next, and the next. People keep ageing. They get hurt and sick, but they never die. The populace of the planet dub this "Miracle Day" for the immortality they now seem to have. However, this leads to a negative result: a population boom, overnight. With all the extra people unable to die and continuing births, resources have become limited. It's suggested that in four months' time, the human race will cease to be viable. But this can't be a natural event – someone must have caused "Miracle Day". It's a race against time as C.I.A. agent Rex Matheson investigates a global conspiracy. The answers lie within an old, secret British institute. As Rex keeps asking “What is Torchwood?", he's drawn into a world of adventure, and a threat to change what it means to be human, forever.