Sir Topham Hatt (a.k.a The Fat Controller) is the controller of the Engines on the Island of Sodor.
Sir Topham Hatt in Thomas & Friends
In Thomas & Friends, there is only one Sir Topham Hatt. He can be described as a combination of the three controllers from the Railway Series. His full name has been given as Sir Bertram Topham Hatt.
In his youth, he was a Boy Scout. Prior to him becoming Controller of the North Western Railway, Sir Topham Hatt owned a Sentinel steam lorry named Elizabeth, who notes that he was not the best driver. When he was a young man, Edward always took him aboard an old coach on his birthday. He also built the Coffee Pots some time prior to Thomas arriving on Sodor. Sir Topham later received his knighthood for his services to the railway industry. He was also the controller of the Skarloey Railway, until Mr. Percival was hired to help him manage the ever-increasing size of his railway industry. Prior to Blue Mountain Mystery, he bought a track inspection car named Winston, who is often used as a private transportation vehicle on the railway.
Sir Topham Hatt married Lady Hatt and is the grandfather of Stephen and Bridget Hatt. He has a twin brother, Sir Lowham Hatt and his mother is Dowager Hatt. According to the Official Website, "we have yet to meet his children".
As well as owning several engines, he owns a cat and a blue car and lives in a mansion somewhere on the outskirts of Wellsworth.