"‘Give me your seat!’ she shouted, taking off her bra and waving it around her head. Then when he didn’t respond she clambered off him and onto the next row repeating her plea for a seat. There were red faces everywhere, some people were giggling, others were just staring with slack jaws. Her voice got louder as she explained she was staging a naked protest about overcrowding on trains. A quick glance down the carriage revealed a pile of clothes and a small placard by the luggage rack, which she had obviously abandoned while we had all been distracted by breakfast and emails.