The Famous Five (1978)

Five Go Off to Camp (1) (1x7)

Air date: Aug 14, 1978

Part 1: Spook trains in the middle of the night! And they seem to vanish into thin air—but where do they go? The Famous Five are on to it. But the discovery of an unusual underground tunnel system, and a train-service, has them puzzled. If they follow the tracks, will they solve the mystery?