In today's episode, Maddie is at a train museum finding out how signal boxes work and how trains are moved from one track to another to get to the right place. Maddie puts her special camera on the front of a train so we can see what happens to the points when the train switches from one track to another. Next, Maddie visits a paint factory to find out how paint is made. She uses her special camera to see inside the huge mixing vat where all the different ingredients are being mixed together, and we see how a computer is used to make all the different colours.