In the eleventh episode, Identity, Ben meets Henry at the harbour after he has shunted the Flying Kipper.
Bill and Ben were annoyed when Diesel came to collect an important train for a "special project". He refers to the the twins as "little engines". The next day, Diesel got his comeuppance when he hits some un-ballasted tracks and derails. Bill and Ben take his train to the Arlesdale Railway.
Bill and Ben helped a fishing boat stranded at sea during a heavy thunderstorm. The harbourmaster tied a rope to the twins and they pulled the boat back into the docks. The fishermen praised the twins for their rescue. The twins also made a cameo appearance in Christmas Delivery.
Ben was spooked of a broken coupling on BoCo's train, as Bill thinks it was the ghost of a quarry workman killed in a nasty accident as said by Edward, but Ben disbelieved it. A lot of things go missing later on and the twins hatched a plan to catch the thief. Later, they startled the thieves with Ben whistling loudly and gave chase only for Bill to find out that the thief was The Fired Workman. He and his accomplice were arrested by the police for breaking into the quarry without permission, stealing and damaging private property.
When Bill whistled to get the workmen out of a near-collapsed China clay tunnel, The SCC Manager disbelieved what was happening with the emergency until a loud bang had gone off within a few seconds. The manager brought Emily Helen Hatt to the quarry and she sent the two twins to work at The Container Yard where James later meets them and told him about the transfer to the container terminal despite the quarry having to be closed for a few months. In Separation Anxiety, Ben felt alone with the work after Bill's accident with a falling container. The cause of the accident from an inspector's point of view to Mrs. Hatt was that the crane had some defects in it. Bill later returned to the yard and was reunited with Ben.
In Last Laugh, their tricks were going too far with a new diesel named Iris and she made them be the targets of her own trick when she was out of their perimeter. The twins returned to the quarry at the end of the episode after the tunnel shaft that collapsed in the first episode was repaired. In Homecoming, stock footage from Separation Anxiety reveals that Bill noticed the missing engine at Crovan's Gate to be someone who will appear as a mentor to the leader of Thomas' Branch Line.
Bill and Ben are based on Alfred and Judy, two unusually low saddle tank engines made by W. G. Bagnall built in 1948.
- Season 1 - Great Western (cameo) and Identity (Ben only)
- Season 2 - Little Engines
- Season 3 - Search Engines (Bill only), Storm Report and Christmas Delivery (cameo)
- Barry the Rescue Engine - A Troubled Engine (Bill or Ben cameo)
- Season 5 - Phantom of the Quarry
- Season 1 STMY - A Change of Scene, The Missing Engine (Bill or Ben cameo), Doncaster Drawn (mentioned, not named), Separation Anxiety, Last Laugh and Homecoming (stock footage, Bill later mentioned)
- Season 2 STMY - Unwanted, Dime For Trouble (Bill cameos), Troublesome Trucks (Ben only, mentioned)
- Bill and Ben received their brand new models based on their Railway Series form by WildNorWester in Season 1 STMY. Before then, they had used Sodor Island 3D's models made for Trainz 2006, which were the best models at the time.
- Bill and Ben were said in Phantom of the Quarry to have arrived in 1966, but the epsiode Unwanted contridicts this by showing them on the island in 1965, when BoCo came. Plus, the events of 'Edwards Exploit' were mentioned in 'Winds Of Change' to have happened in 1965, and Bill and Ben were on the island then too.