|“||It's Donald and Douglas, sir. They say, sir, that if you send them away, sir. They'll be turned into scrap, sir. That would be dreadful, sir! Please, sir. Don't send them away, sir. They're nice engines, sir!"||„|
|~ Percy to the Fat Controller, The Deputation, The Twin Engines|
Giving long and stalwart service, Donald and Douglas eventually became 57646 and 57647 on the Scottish Region of British Railways. In 1959, Sir Topham Hatt needed a goods engine and by his request, BR transferred 57646 (Donald) to Sodor.
To Sir Tophan Hatt's surprise though, two engines arrived. Donald's twin Douglas (57647) could not stand to be separated from his brother, and was smart enough to realise he would eventually be scrapped if he stayed in Scotland. Neither engine could be told apart: both claimed to have forgotten their numbers, and indeed their numberplates had "slyly slipped off" during the journey from Scotland, forcing Hatt to keep both until he could determine which engine was freeloading on his hospitality. It was later revealed that this piece of skulduggery had been planned not only by the two engines, but also by their drivers and firemen, who were all related. The Fat Controller was unaware of Douglas' motive and threatened the two that whichever engine he found out to be the truant would be sent home. Both engines resolved to give outstanding service so that Hatt would want to keep both of them. This plan quickly went to pieces, however, after Douglas accidentally shunted Thomas' special coach, full of passengers, into a siding at Tidmouth, causing a great deal of fury for the passengers. Things were more complicated when Donald crashed into a signalbox at Tidmouth and Douglas destroyed the Spiteful Brakevan. Despite all this grief, the twin's professionalism, competency, strong work ethic, and personable natures had begun to win them support, particularly when they demonstrated an aptitude for snowplough work that they had learned in Scotland. After rescuing Henry from just such a snowy ordeal, the other engines came over to Donald and Douglas' side which ultimately led to the engines of Sodor taking industrial action. After a suggestion by Edward, and being pushed into it by Gordon, Percy was presented to the Fat Controller as a deputation, arguing the twins' case on their behalf and pleading that, if sent away, they would be scrapped. Hatt's reaction to this was mixed - though he understood the engines' feelings he did not approve or appreciate them trying to interfere with his decision-making. However, Percy's statement and the twins' excellent performance was enough for Hatt to take pity on the twins and keep both. He demonstrated this intent with an offer of a fresh coat of paint for both engines, and by their request they were painted NWR blue.
Since then, the twins have, by all accounts, "transformed" goods traffic on the main line. Such is their versatility that they regularly see service on Duck and Edward's Branch Lines, as well as duties as station-pilots at Tidmouth. A turntable has been provided for them at Arlesburgh, although briefly decommissioned after Oliver was pushed into it by some trucks.
Such a demanding work-load has begun to tax them, however, and in 1993 the Fat Controller borrowed a navy saddletank named Wilbert from the Dean Forest Railway to deputize for them on the Arlesburgh branch, with the intention of at some point obtaining another engine of Wilbert's class to permanently fill that role.
Donald and Douglas are practical and level-minded characters who nevertheless enjoy a joke, especially impersonating one another - the fitting of the twins with nameplates was done to specifically end this element of their humour. Their tendency for jokes, however, has continued and both display a keen sense of wit and, where necessary, an acid tongue. In their work, however, their performance is exemplary and they can be described as some of the most well-regarded engines in service on the railway, comparable with Duck and Edward in their reliability. Donald and Douglas understandably held a grudge against Diesels for a time - after all, the oil-guzzling engines were taking over their work - but after BoCo helped them in Edward's absence, they have agreed that there is nothing wrong with Diesels on the whole.
Donald and Douglas are based off of the Caledonian 812 class 0-6-0 tender locomotive.