Set in the carriage of a moving London underground train. Two youngsters, an old lady, and others if extras can be afforded. At one of the stations a thuggish young man enters and begins to smoke. Smoking is forbidden. The old lady challenges him to put it out. He refuses. She asks the others to join in with her protest. No one dares. She threatens to pull the cord to stop the train. The thug intimidates her. Everyone waits to see if she'll pull the cord.