Guy works to get a Yorkshire saw mill up and running again, and then use it to make a replica of one of the less-celebrated inventions of the Victorian era: the first pedal-powered bicycle. Using his engineering skills, Guy helps the restoration team repair the ingenious water turbine that's needed to power the whole of Gayle Mill in Wensleydale, but which is currently leaking 43 litres of water a second. He ropes in his old mate Mave, who's a carpenter, to help fell a tree by hand, transport it to the mill on a steam traction engine and then use it to make his bike. Along the way, Guy learns about the lives of factory workers: the foot soldiers of the Industrial Revolution. He discovers how the mechanisation of farming left many with no choice but to head for the new industrial cities and towns and how child apprentices were often little more than slave labour. If Guy can get the mill running and build his bike, it'll need a test run and, as Guy is a man who likes a bit of an adrenalin rush, this is unlikely to be a gentle trundle across the dales!