As I locked the gate to the allotment, I noticed that it was the 1880s outside. The cars had vanished, and there was an opium den across the street. A bicycle rickshaw was struggling up the hill and I saw three tiny mice wearing Beatrix Potter-style outfits, holding on to the roof straps. They were swinging and squealing happily. I cheered and clapped. It was the famous music hall mice that all of London had been talking about.