The Fat Controller is a short, stout gentleman. He is usually dressed in a black suit with grey trousers, a cream or yellow waistcoat, a black tie, and a top hat. He is most often depicted as having thinning grey hair and blue eyes.
Lady Hatt occasionally helps her husband with railway business, and the engines sometimes go to extreme lengths to help throw parties for her birthday. She likes the railway, but had a certain dislike for Annie and Clarabel until they were cleaned and repainted. Although her husband runs a railway, she likes a day out on a boat or in their car.