Dart assists Den in running the Sodor Dieselworks.
Dart is Den's fast and feisty assistant at the Dieselworks. Dart has worked with Den for so long he can read Den's mind. Together, they run the Dieselworks well. Dart will quickly explain what Den is trying to say. No other Diesels know how to fix an engine as quickly or as capably.
In Day of the Diesels, Dart complains about needing a new crane and hides Flynn's hose in the garbage by order of Diesel 10.
In the fifteenth series, he went with Den and Diesel to Misty Island in search of a Christmas tree for the Dieselworks. Dart later teased Flynn for spraying Edward and his driver. When he and Den were classified as weather reporter engines, Dart told everyone, including Thomas, that a big storm would be on it's way which was actually a lie and liked to pull pranks on the other Diesels. Dart then thought that he would rather give up being a Diesel and be a steam engine instead but his idea didn't go as he had planned so he decided that he rather liked being a Diesel. It was then Dart complained of being told what to do by Den for not doing as he was told. In winter time, Dart ran into Skarloey and he was told to work hard but because of the Troublesome Trucks pushing him, Dart was derailed and Den had to fetch Rocky to put him back on the rails. Dart later ran out of fuel when he was coming home with some spare parts for the Dieselworks and Flynn the fire engine had to tow him home. When Dart was sent to Misty Island to work with Bash, Dash and Ferdinand, A huge rockslide blocked the entrance to the tunnel he was in and none of the other engines knew where he was and he was trapped in there but luckly, Den, Thomas,Rocky,Jack and Alfie decided to come to his aid and they removed all the rocks and Dart was free. Later on, Bash and Den went to take the children to the beach while Dart was leaved on his own to work at the Smelters but Arry and Bert shoved him for being a scaredy engine and he nearly fell into a fernece but Belle came and pulled him away. Dart can be cheeky but is very kind.
Dart likes jokes, much to the annoyance of the other Diesels. He is usually cheery, but he can still get grumpy and irritable. However, Dart is a valuable member of the Dieselworks team, and is an able helper to Den, but like a lot of the other Diesels, he can be cheeky and rude to some of the other engines...
Dart is based on an 0-4-0 Diesel-hydraulic locomotive built by Bagnall.
- Rupert Degas (UK/US; Day of the Diesels onwards)
- Dart's catchphrase is "Dizzy Diesels!".
- In Vinesauce Joel's Windows 7 Destruction Stream, Joel says about a MIDI download avatar featuring Dart's face "This is the worst image." [img]http://i.imgur.com/zOmJCjW.jpg[/img]