Emily is a Stirling Single tender engine. She works mostly on the Main Line and once ran the Misty Valley Branch Line. She also has her own set of coaches. Emily acts as a sisterly figure to the other engines, and though she can be bossy at times, she has a big heart.
When Emily was a new engine on Sodor, she was ignored by the other engines for pulling Annie and Clarabel without Thomas' permission or knowledge. The matter was resolved after she saved both Thomas and Oliver from a nasty accident on the cross-points, and she was rewarded with two new coaches. Emily proved to be kind-hearted, as she was the only engine concerned about Henry when he was ill due to leaky tubes and when she stuck up for Salty when Thomas and Percy were teasing him.
However, Emily has proven to be a nuisance on occasion as she bossed everyone about when they were clearing up after a storm; Thomas when taking passengers, and Percy when shunting trucks. When pulling the express for the first time, she was determined to keep to Gordon's timing, only to run out of water.
When Thomas had to stay at Knapford Sheds, Emily did not like his company at first as she just wanted some sleep. However, she learned how comfortable it is to have the company of friends and once Tidmouth Sheds was rebuilt, she was transferred there to be with her new shedmates.
Like most engines, Emily can get quite puffed up in the smokebox. When she was called "Excellent Emily", she ignored the advice of Murdoch, Thomas, and Duck only to get herself into trouble. Afterwards, she took their advice to get her job done.
Emily tries her best to make her friends happy. When she assumed that Mavis was sad, she took flowers to the quarry, but only created a mess. When she tried to help her friends with the football/soccer match, she neglected to fetch the dirty washing, which turned out to be the football/soccer team's uniforms. Also, when the Fat Controller lost his top hat, Emily went to find it without success and then took the special Christmas train without permission. However, she always makes amends for her friends' sake.
When Thomas hid his snowplough, Emily had to do Thomas' work and saved him when he got stuck in the snow again.
Thomas told Emily about the "Flatbeds of Fear," but Emily did not believe in it and said there was an explanation. She eventually believed in it, until Thomas told her that it was just one of Salty's tall tales.
When the Steam Team tried to clear the tracks of snow for Connor to deliver the last train for Christmas, Emily was unable to clear them from the Sodor side, but was happy to see Hiro as he cleared it from the other direction, then was disappointed when they mistook Harold for Father Christmas by believing his red port lamp to be Rudolph's nose.
She was later informed by Paxton about the rumour that Toby was to be scrapped, but Henrietta overheard and knew it wasn't true. Emily took her to find Toby, and once they found him safe, Emily gave him some of her coal.
She became fascinated with Caitlin being able to go at such high speeds and wondered what it would be like to be fast, becoming depressed when she could not do so. However, in the end, she managed to save Caitlin when she descended down a steep hill with broken brakes.
When Thomas was fed up with Diesel's selfishness during the holidays, Emily partook in his plan to mend the diesel's ways, much to her joy and amusement. She later attended the Earl's Christmas lunch with several other engines, including Thomas and a reformed Diesel.
Emily would then go on to be part of The Great Railway Show, competing in the Best Decorated Engine Parade along with James, Carlos, Rajiv, and Yong Bao.
In the seventh season, Emily acts as a sisterly figure to the others. Emily is kind and friendly and always sensitive to the other engines' feelings. If she wrongs someone, knowingly or not, she is quick to apologise.
From the eighth season onwards, however, Emily can tend to get into trouble because of her fussy and bossy attitude, but she is nicer than she lets on. She seems to want to strive to be one of the best, and it sometimes causes mishaps, though she usually makes up for her mistakes when she realises her errors.
From the seventeenth season onwards, however, her personality has reverted more to how it was in the seventh season.
Emily is based on a GNR G3 Stirling Single. The only surviving member of her class (No. 1) is on display at the National Railway Museum.
Emily is painted emerald green with gold and yellow lining. She has chocolate running-boards and her buffers were originally bronze but are now silver. For The Great Race, gold trim and flowers were added to her coat for her participation in the Best Decorated Engine Parade.
- Teresa Gallagher (UK (Hero of the Rails onwards))
- Jules de Jongh (US (Hero of the Rails onwards))
- Blanche Ravalec (France and French speaking Canada (eighth season onwards))
- Diana Pérez (Latin America (Hero of the Rails onwards))
- Although the second female steam engine to ever appear in the television series (the first being Lady), Emily is the first female steam engine to appear and remain on a regular basis.
- Michael Angelis, Pierce Brosnan and Teresa Gallagher give Emily a Scottish accent reflecting the origin of her designer.
- One of Emily's models was on display in Canada at Nitrogen Studios, it is now part of the touring Thomas and Friends: Explore the Rails exhibit.
- Emily is the first character besides Thomas himself to say his phrase, "Cinders and ashes!", which was done in the thirteenth season episode, Tickled Pink.
- Some literary articles show her being sisterly mostly to Thomas and James: according to a magazine bio, she has a particular fondness for James and treats him like a little brother. In Railway Rhymes, the author states that Emily and Thomas act like brother and sister.
- Amazingly, both she and Thomas have wanted to become streamlined at some point in the CGI Series.
- Emily is the only member of the Steam Team to not be created by Wilbert Awdry.
- According to "Emily's Slide Show", she was built around the same time as Donald and Douglas.
- Emily's seventh season whistle sound would later be re-used for Peter Sam and Freddie.
- Emily had the same whistle sound as Henry in the eighth season and from the thirteenth season until the latter half of the seventeenth. From the eighth to twelfth season, her whistle was a pitched-up version of Henry's. From the seventeenth season onwards, she receives a new whistle sound.
- Her whistle was also used in the Mr. Men Show episode "Parks".
- Before Big World! Big Adventures!, Emily was the only member of the Steam Team not created by Wilbert Awdry, as well as the only female member and the only member who was not introduced in the first season. She is also the only member to not have a number.
- Although Emily does not have a number on her tender, she is incorrectly listed as being the number 6 engine on The Official Website
- According to Robert Gauld-Galliers's concept art, Emily was originally going to have handrails on top of her smokebox, three front coupling chains and a gold builder's plate on her wheel arch.
- Emily was called Emilie in the French dub of the seventh season.
- Emily had many modifications throughout the television series. These include:
- Season 8:
- Her buffers changed from bronze to silver.
- She shares the same whistle sound as Henry.
- Season 9:
- Season 11:
- Her forward buffer housings' colour changed from black to red.
- Season 12:
- Her face became larger.
- Hero of the Rails:
- Her face became a bit thinner.
- Her whistle sound is the same as Henry again.
- Season 13:
- Steam incorrectly emits from her safety valve.
- Tree Trouble:
- Steam no longer comes out of her safety valve.
- No Snow for Thomas:
- She gains a permanent headlamp and tail-lamp, as well as lamp irons.
- She gains a new whistle sound, which sounds almost identical to her seventh season one and is actually Stephen's in a higher pitch.
- Season 19:
- She gains brake pipes.
- She received more prominent front and rear brake-pipe outlets. Strangely, the front ones that have been there since she was introduced have not been removed.
- Her side rods became silver.
- Snow Place Like Home and parts of Best Engine Ever only:
- Her brake pipe faces downwards.
- Season 8:
- In "Best Engine Ever", Emily dreams of being a streamliner.
- Will You Won't You (performed)
- Be Who You Are and Go Far (performed)
- The Most Important Thing is Being Friends (performed)
- ERTL (discontinued)
- Wooden Railway (normal, talking, roll and whistle, and streamlined)
- Take Along (normal and metallic; discontinued)
- Motor Road and Rail (discontinued outside Asia)
- TrackMaster (normal, Splish, Splash, Splosh! and Snow Clearing versions)
- My First Thomas (normal and talking)
- Hornby (discontinued)
- Bachmann (HO and large scale)
- My Thomas Story Library (discontinued)
- Trading Cards
- Take-n-Play (normal and talking)
- Limited Edition Collection
- Mega Bloks (discontinued)
- Capsule Plarail (normal and metallic)
- Pocket Fantasy (discontinued)
- Woody Capsule Series
- Boss (with Milk Tanker; discontinued)
- Collectible Railway
- Padlock and Key
- Micro Rubber Engines
- Minis (classic, spooky, DC super friends and sweets)
- Rail Rollers