The Boy Who Turned Yellow

John (Mark Dightam) loses one of his pet mice, Alice, whilst on a school trip to the Tower of London. Upset back in class, he is sent home by his teacher for not paying attention during a lesson on electricity. Later that day on the London Underground, the train and everyone in it suddenly turns bright, vivid yellow. John's doctor (Esmond Knight) declares that the condition is harmless and should wear off soon, but that evening John hears noises from his television set and meets the eccentric yellow-coloured Nick (short for Electro''nic'') (Robert Eddison). The pair return to the Tower of London in an attempt to find Alice, but they are menaced by Yeoman Warders and John is threatened with execution. When John is finally reunited with his pet, he awakes in class. Was his adventure actually all just a dream?