In this, the twentieth book of Awdry's, we are taken right back into the history books, and shown the background of bouncy Skarloey and his altogether more cautious brother Rheneas, right from their building, right through their working lives, to the time of the books publishing, in 1965. It also gives us a clear insight into Awdrys policy of Sodors narrow gauge railway mirroring the real-life Talyllyn Railway, in Wales.

Crosspatch
The story opens in a shed scene, where Skarloey and the engines are being polished and cleaned, ready for a days work. Nancy the cleaner is polishing him when Skarloey offers to tell her a story about his past.  The reader is introduced next to Talyllyn and Dolgoch, Skarloey and Rheneas's 'identical twins', of the Talyllyn Railway (who of course, Awdry based them upon). Skarloey is sent away to Sodor, to begin work on a mineral railway. He is disgusted at having to pull trucks (preferring nice quiet coaches), and refuses to steam: even the efforts of Mr.Mack, the manager, come to nothing.  After a few days the staff give up, and sheet poor Skarloey up, until he becomes "a better engine" - stubborn Skarloey suddenly feels more than a little silly.  At this point, we return to the present day, to discover that a small crowd has gathered around Nancy, listening to his story!
 
Bucking Bronco
The manager decides to give him a second chance, and has brought in a man called Mr.Bobbie, an ex-employee at Fletcher Jennings of Cumbria (where the engines were built) to cheer up Skarloey. The trick works, and together they pull trucks all day, to make the line ready for when Rheneas finally arrves. Later the railways directors are visiting the railway, and Skarloey is excited to find out that he is pulling the special train: Rheneas however is wary, but Skarloey will not listen.  All is well until the return journey, when the manager steps onto the footplate and is a little heavyhanded in his handling, and although Skarloey is excited as speed begins to pick up, without a trailing wheel beneath his footplate, and travelling backwards, he begins to bounce alarmingly as the speed rises. The Manager, alarmed, shuts the regulator, causing the coaches to slam up violently, against poor Skarloey, which made the coaches angry: together, they surge deliberately into him, causing the Manager to fall clean off the footplate, and land upside down in a bush at the lineside!  He is not hurt, but cross - Skarloey remains out of sight for the remainder of the Directors visit in disgrace, and Rheneas pulls all their trains.  Although the directors are not clearly not happy with Skarloey, an inspector is called to solve the problem, and he reccomends fitting a set of trailing wheels beneath his cab to prevent further trouble - he is relieved to find out that the directors are no longer angry with him!
 
Stick-In-The-Mud
Skarloey is duly returned to the works at Fletcher Jennings, where he recieves a new set of trailing wheels beneath his cab, to prevent him bouncing, as well as being fitted with a cab too. On his return, he boasts no end to Rheneas, causing jealousy - to the point that the two refuse to speak to each other.  One wet Monday morning, Skarloey is called upon to haul the workmans train up to the Quarry.  Rheneas is rudely awakened an hour later however, with news that Skarloey has run into a landslide and is stuck! Rheneas is initally reluctant to go and help him, but after persuasion he sets out, to rescue the marooned workmen. To Rheneas's amazement, his brother humbly apologises for being swanky, before suddenly starting to giggle - realising he is covered in mud, he retorts "I'm the stick-in-the-mud, not you!", and they both begin to helplessly crack up with laughter. Still laughing, they make up, and are friends again.
 
Duck & Dukes
It is revealed that it is Rheneas and Skarloey's one hundredth birthdays, and that preparations are underway for the celebrations.  A Duke is arranged to come and open the grand extension to the railway, however Duck is worried - thinking of the GWR locos which are all scrapped!  He tells Peter Sam who scuttles off to the shed to tell the others.  When he gets there though, preparations are already underway for the great day, and the Thin Controller is assigning jobs to the engines. A TV company are coming to the railway, and are to film the event! Come the special day, Rheneas hauls a re-enactment train of the one which opened the line, with the passengers in Victorian costume, whist Peter Sam hauls a train in front with the TV Cameras on board, filming. Peter Sam, meanwhile, is still curious after what Duck said however, about whether this Duke can be real or not, and when he finally does meet the man, he duly asks him outright.  The Duke explains that Duck was thinking of a Duke as a Great Western engine, not a real person - and that he was a real duke! And so, he wishes the two brothers a happy life in the future, and good running.  Skarloey then makes a speech in honour of his brothers in Wales, and to quote him, "Please go and see them, you Grace, and everybody, and wish them many happy returns from Skarloey and Rheneas, their 'Little Old Twins'."