Episode 2

Peter Snow and Dr Hannah Fry present live from Didcot Railway Centre. Peter is joined by Bob Gwynne, curator at the National Railway Museum, to apply his incredible knowledge of the British rail system to the live images coming in. Hannah is out and about at Didcot, working out the equations that meant that the move from steam to diesel power was inevitable. She also meets Sir Kenneth Grange, the man responsible for many design classics including the famous Intercity 125 which is this episode's focus for the spotters up and down the country. Dick Strawbridge is on the hunt for a very special example of that train in Swindon, and also meets the group trying to buy and preserve the original prototype. Tim Dunn has moved south to Carlisle to spot one of the trainspotters' favourite locomotives, the Class 37. All of this, plus a man that has collected thousands of locomotive number plates and a short film about the 'flying banana'.