Bill and Ben were built in 1948 and arrived on Sodor in 1961 to work in the China Clay Works. They took the clay from the Clay Works to either Brendam Docks for ships or Wellsworth Station for engines on the main line. One day in 1965, they're trucks were mistakenly taken by a diesel. Bill and Ben thought the diesel had "magiced" them away. They hurried to Wellsworth to play tricks on him by pretending there was only one of them. After finding out it was a big misunderstanding, they apologized to the diesel, who turned out to be named BoCo. Not long afterwords, Gordon was accidently sent along the branch line into the harbour. Bill and Ben joked that they thought he was scrap and threatened to dump him in the sea. Gordon, on the other hand, thought the twins were serious and panicked. Boco "saved" him in the end. Since then, the twins have played tricks on several engines, including Thomas, Fergus, Connor, and Timothy.
In the late summer of 2013, there was nonstop heavy rain drenching Sodor. Bill and Ben like the rain, and they were very pleased. However, a flood warning was issued and the twins helped evacuate the China Clay Works. Just as they got out, they realized that there were still men in the mineshaft. Despite strong urges from Edward and BoCo not to do so, the twins went back and rescued the workmen. They got out just in time, and were praised for there extreme bravery. A plaque was placed in their sheds to commemerate this.
In Season 1 of TEOS and How the Diesel Stole Christmas, SI3D's 2006 models of Bill and Ben were used. When they returned in the 2nd season (Episode 14), Hilltracks Trainz Routes's models were used. From More Branch Line Engines, (#1TFM)'s models of Bill and Ben are used
The twins are based on Bodmin and Wenford Railway's 0-4-0ST "Alfred" and "Judy".
Of all the engines on the Island of Sodor, Bill and Ben are notorious for being the most mischievous (not counting malicious engines like Diesel). They love playing tricks on engines and will not miss a chance to do so. They also can be very irritable and can sometimes not get along very well each other. The Twins appear to be slightly unintelligent as well. But, they do take pride in their work and their tricks are never malicious.
- The Great Railway Heist (Bill only, cameo)
- A Turning Point for Edward
- End of the Line for Edward (appear in post-credits scene)
- How the Diesel Stole Christmas (Stock Audio)
- The Search for Smudger (cameo)
- The Most Famous Engine (both cameo in Part 1)
Bill and Ben will both likely appear in Revenge of the Ghost Train
T1E2H3's RWS AppearancesEdit
- SamTheTrainFan: Episode IV-How the Diesel Stole Christmas
- DarthWill3: Episode XV only
- Thomas1Edward2Henry3: Episode XX-Present
Bill and Ben were introduced in the second season episode The Diseasel and appeared in every season since until the thirteenth except the eighth. They did make a cameo in a deleted scene in that season, however. They then re-appeared in CGI in Season 17, and appeared in every season since, except the twentieth. They are both voiced by Johnathan Broadbent in both dubs.