This actually happened I was a station worker at Oxford station I had to check the trains that came in to go out of service to the depot as I was walking through one end of the train the cleaner walked through from the other way when saw him I presumed the other end was empty so I got off halfway and told driver to go. The cleaner stayed on the train to clean it then came on radio to say there was someone left on the train and you’ll never guess who it is it’s terry Waite the guy that got held hostage in Lebanon. Obviously my manager had to go over and sort it out