1916: the Western Front. Private Percy Blakeney wakes up. He is lying on fresh spring grass. He can hear birdsong and the wind in the leaves in the trees. Where has the mud blood and blasted landcape of No Man's Land gone? 2015: Madison Wisconsin. Cop Monica Jansson is exploring the burned-out home of Willis Linsay a reclusive - some said mad others dangerous - scientist. It appears to be arson but the firemen to have caused more damage than the fire itself. There's no sign of any human remains in the wrecked house but on a mantlepiece Monica finds a curious gadget - a box containing some wiring a three-way switch and a...potato. It is the prototype of an invention that Linsay called a 'stepper'; an invention he put up on the web for all the world to see - and use - an invention that would change the way Mankind viewed his world for ever. And that's an understatement if ever there was one...Because the stepper enables the person using it to step sideways into another America another wherever that person happened to be another Earth. And if the person using it keeps on stepping they keep on entering even more Earths. This is the Long Earth. It is our Earth - and a chain of parallel Earths each differing from its neighbour by sometimes very little (or quite a lot). It's an infinite chain offering 'steppers' an infinite landscape of infinite possibilities. And the further away a stepper travels the stranger - and sometimes more dangerous - the Earths become. The sun and moon always shine the basic laws of physics are the same. However the chance events which have shaped our Earth such as the dinosaur-killer asteroid impact might not have happened and things may well have turned out rather differently.And until Willis Linsay invented his stepper only our Earth hosted mankind. Or so we thought. Because it turns out there are some people - such as Joshua Valiente - who are natural 'steppers' who don't need a stepper to explore these other Earths. Joshua's a pioneer and and the possibilies are of course endless. Just be careful what you wish for...