Percy

Percy is a cheeky green saddle tank engine who was brought to Sodor to help run the railway during the big engines' strike. His favourite job is to deliver the mail. He works on Thomas' Branch Line as a goods engine.

Personality
Percy is a rather cheeky, but kind engine, and generally behaves well, except when he is getting into mishaps from being over-eager. He loves teasing the others, especially the bigger engines, such as Gordon and James, but is always brought down to earth in due course by anyone who gives him the moral to learn, especially the Fat Controller.

As the television series has progressed, Percy has been dumbed-down in order to teach viewers difficult words: he would say "dingy-fried" where anyone else would say "dignified," "demonstration" into "dimer-station," "railway inspector" into "railway inspectacles," "new-fangled nonsense" into "new-funneled nuisance", "action" into "act-on", or "V.I.P." into "V eyed-p." He is also shown to make silly mistakes, but then fix them upon realising what he has done before further damage is caused.

Percy is incredibly accident-prone and has many accidents, sometimes due to his own silliness or his tricks backfiring. He holds the dubious record of the most accidents in one season - five, in the second season - crashing into some buffers, falling into the sea, being pushed onto a brake van, colliding with a cart, and being hit by a falling crate of treacle. So far, his silliest accident yet was in the sixth season, when he slipped on oily rails and crashed through the chocolate factory and emerged covered in chocolate. Despite this, he always tries to do his best, learn from his mistakes and get his jobs done, a loyalty which Sir Topham Hatt has praised him for on several occasions.

Although their friendship has been turbulent at times, Thomas is generally portrayed as Percy's best friend, he is also good friends with Toby as well.

Since the second season, Percy has had a small rivalry with Harold, stemming from their race. However, they are always willing to help each other when in trouble.

He also had held a grudge from the big engines about their tricking him into misinterpreting a signal, but silenced this with some help from Duck. This shows that, when nonsense goes too far, Percy will not stand for it and seek help to settle the matter for good, even if he faces a reprimanding from Sir Topham Hatt for it.

Basis
Percy is an 0-4-0 saddle tank believed to have been built originally by the Avonside Engine Company of Bristol but prior to being purchased second or third hand by Sir Topham Hatt he acquired components from Hunslet of Leeds and other builders.

Trivia

 * One of Percy's models is currently on display in Japan at the Hara Model Railway Museum (previously on display at Nitrogen Studios), along with his large-scale model used for the spin-off series, The Pack (previously on display at Thomas Town).
 * Percy is the only engine who is known to have been named by the Fat Controller.
 * In the Greek narration of the Classic Series, Percy is called "Jerry". From the thirteenth season onwards, Percy has been referred to with his original name.
 * According to Abi Grant on her website, Percy is her favourite character.
 * Britt Allcroft stated he was also her favourite (due to him being green and cheeky).
 * He is also Mark Moraghan's favourite character, alongside Cranky.
 * Percy's Big Loader model has had three cameos in the American sit-com, Everybody Loves Raymond.
 * Percy's whistle sound is actually Edward's in a higher pitch.
 * Percy is the first character other than Thomas to be the protagonist in a special, with that special being Day of the Diesels, which he would later do again in Tale of the Brave.
 * In Thomas and the Rumours, Percy is stated to have a branch line although Thomas' branch line may be the one that was referred to.
 * Percy was featured on the 1986 single cover along with Rheneas of Oh L'amour, a song by English synthpop duo Erasure.
 * One of Percy's original face masks is owned by Twitter user ThomasTankMerch.
 * Percy went through several aesthetic changes in the television series:
 * Season 2 (only):
 * His right side piston was loose and would shake violently when moving.
 * His centre lamp iron was heavily glued in.
 * Season 3:
 * His whistle changed shape (now being more like Gordon or Henry's).
 * Later in the season, his whistle sound would be his own but in a whole step lower in pitch.
 * His two front sandboxes were flipped around.
 * Season 4:
 * His whistle sound changed back to its original pitch.
 * His smokebox was raised up.
 * In some episodes towards the end of the season, one of the two black sections extending from under his smokebox to the end of the footplate is missing.
 * Thomas and the Magic Railroad:
 * He gained a permanent lamp.
 * He gained a stand underneath his smokebox.
 * The lining on his pistons was moved slightly inwards.
 * His eyebrows change shape.
 * Season 6:
 * His cab was blacked out (except for cab shots filmed on a larger model).
 * Jack and the Sodor Construction Company (large scale model only):
 * The step ladders on his running board are painted red.
 * His whistle is taller than his cab.
 * His dome is painted green.
 * Season 7:
 * The counterweights on his wheels vanished.
 * The Great Discovery:
 * His large scale model's dome is painted gold.
 * Season 12:
 * His large scale model's stepladders were painted green.
 * Hero of the Rails:
 * His cab became open again
 * Season 19:
 * His side rods become silver.