Donald and Douglas (originally known by their numbers, 57646 and 57647, respectively) are twin Scottish mixed-traffic engines.
Donald and Douglas are cheery, friendly, and helpful. They like jokes too. They do however get the job done in the end and are a valuable assit to the Fat Controller's railway.
Donald and Douglas are painted BR black and have remained in this livery ever since.
- Season 2 - Donald and Douglas the Scottish Twins, Normandy and Tom (Donald only; cameo), The Great Western Engines (Donald; does not speak; Douglas; mentioned), A Magical Tale (Donald only; cameo), and Thomas and the Snowy Surprise
- Season 3 - Harvey Saves the Day (Donald only; cameo), A Bad Day for Harold (Donald or Douglas; cameo), Elizabeth the Lost Lorry (Donald only; cameo), Trouble Twins, Percy and the Garden Gnomes, and Thomas the Jet Rocket Engine (Donald only; cameo)
- Season 4 - Percy Saves the Day (Donald only; cameo), Edward's Steam Fair (Donald or Douglas; cameo), Shortcut to Castle Loch, Salty's Story (Douglas only; cameo), Murdoch's Heavy Train (Donald; deleted scene; Douglas; cameo), Harold to the Rescue (Donald only; stock footage cameo), and Gordon and Spencer the Fast Engines (Douglas only; cameo)
- Season 7 - Trucks (Donald only; cameo), Oliver's Sea Rescue (mentioned), Duncan's Dilemma (cameo), Party at Castle Loch, and Dusty Rusty (Donald only; cameo)
- Gordon and Spencer: An LNER Rivalry (Douglas only; stock footage cameo)
- The Engines Split (cameo)
- Oliver's Escape
- Their original numbers are an in-joke; the BR numbers only went up to 57645.
- DonaldDouglasandOliver11 stated that Donald and Douglas were one of his favourite characters, along with Edward, Henry, Oliver, Toad, Rheneas, and Duck.
|North Western Railway|
|Thomas • Edward • Henry • Gordon • James • Percy • Toby • Duck • Donald and Douglas • Oliver • Geoffrey • Harvey • Emily • Fergus • Arthur • Murdoch • Molly • Neville • Rosie • Whiff • Billy • Stanley • Hank • Flora • Victor • Charlie • Scruff • Belle • Porter • Glynn • Ryan • Diesel • Daisy • BoCo • Bear • Dave • Derek • 'Arry and Bert • Diesel 10 • Salty • Dennis • Den • Dart • Sidney • Paxton • Norman • Philip • Flynn • Winston • Stafford • Jeff • Angus • Taro •|