Before the replica of Locomotion No.1 can move, Guy joins the team to lay fresh rails, ease the engine out of the workshop and get a fire going in its tiny boiler. After a year of graft, the pressure needs to build to 50 psi before anything turns — but with a stubborn firebox and hours slipping by, it’s clear the engine has other ideas. Heat, soot, oily rags and a fair bit of head-scratching follow as they try to coax the world-changing design back into motion. | Guy Martin