In 2546 the population has risen to 35 billion. All cities and transport systems are underground and vast farms cover the surface. Seven people on a train journey from the UK pass through an underground network of tubes on their way to the Himalayan Mountains. On the journey, the seven must contend with a catastrophe that will change all their lives forever. During the journey, a meteor strike in Ukraine causes widespread devastation. When the travellers reach their destination, they realise all is not well on the outside and set to work immediately to help other travellers who are arriving. But shortly after the last travellers arrive, a meteor storm starts, pounds the surface of the planet for three days, and ends life on earth as they knew it. After finding they are completely isolated, the remaining few are left to pick up the pieces and create a new civilization in the Himalayan Research Centre. For the lucky survivors, it is a new beginning-one that will challenge everything they know.