Henrietta worked with Toby on their old tramway in East Anglia. She became depressed when buses and lorries took over her work and when their line closed, due to the lack of passengers and freight, Toby could not bear to leave her behind. So Toby brought her with him to the North Western Railway. He mentioned to the Fat Controller that a stationmaster on his tramway wanted to use her as a hen house, but the Fat Controller agreed that "that would never do."
At first, Toby and Henrietta were teased by James for having shabby paint. However, Toby and Henrietta later received new coats of paint for their hard work and James stopped teasing them after he crashed into some tar wagons and spoiled his own paint. When Daisy was brought to Sodor, she insulted Annie, Clarabel and Henrietta when she found that she had to share a shed with them. Percy and Toby were forced to take them away and stay up half the night trying to soothe their hurt feelings. Later, she was used as the Fat Controller's private coach when the engines took a big trip to the Other Railway.
Henrietta is often used to carry quarry workers to and from Anopha Quarry. Once, some workers had to crowd on Henrietta's balcony. However this caused controversy with a Policeman, who informed the quarry manager of a by-law forbidding passengers to be carried on coaches' balconies. This problem was resolved when the Fat Controller restored an old coach named Victoria to help Toby and Henrietta. Together they formed "Toby's Vintage Train".
In the television series, the villagers loaded her up with paint pots and presents to give to the engines as a token of gratitude for their hard work in the snow. During a snowstorm, Henrietta allowed Farmer McColl's sheep and newly-born lambs to warm up inside her cabin until the snow thawed. Sometime afterwards, Toby and Henrietta attended the Great Waterton tram parade, alongside Flora and her tram coach.
In the eighteenth season, Henrietta helped Toby get over his fear of Knapford junction. Thomas was sent to pull her (unseen) when Samson accidentally took the express coaches by mistake, because Gordon had to take Thomas' coaches, Annie and Clarabel.
In the nineteenth season, she advised Toby to go to the Steamworks to fix his wobbly sideplates and also told him to fill up with coal on his way to the scrapyard, which he did not. She later heard Paxton talking to Emily about Toby being scrapped and knew that it was nonsense. Emily took Henrietta to the scrapyard where they found Toby safe, but out of coal.
In the twenty-first season, after Toby took her to the Steamworks to getting her seats refurbished, Toby was given a replacement carriage named Hannah. After she had finished her new seats fitted, Toby took Hannah to the Steamworks to be mended, where she reunited with Hannah and revealed to Toby that they were sisters. Afterwards, she began working with Toby once again.
Henrietta is Toby's faithful coach, who likes to be full of passengers and take them on journeys. She does not like to be separated from Toby, although she rarely carries a full load of passengers. Henrietta is quite content with her life on the Island. Toby is attached to Henrietta and always takes her with him, as he says "she might be useful one day".
From the eighteenth season onwards, Henrietta is seen motivating and encouraging Toby when he feels nervous about the capabilities of his work and performance.
Henrietta is based on the GER Wisbech and Upwell Tramway 4-wheel coach. From the beginning, the Wisbech & Upwell used its own special passenger stock. Initially, only four wheelers were used, but bogie coaches were introduced in 1884. The coaches had balconies at each end and a drawbridge type gangway between coaches. Each balcony had an emergency hand-brake wheel. The coaches looked squat and low-lying due to the need to handle raised track and the absence of platforms at some of the depots. All the four-wheeled coaches were scrapped by 1948, but the bogie coaches survived into BR. One of them, No.7, has been preserved by the Midland & Great Northern Joint Railway Society.
Hannah is also based on this rolling stock.
In the Railway Series, Henrietta is painted brown with red bufferbeams and a grey roof. During her days with Toby on his old tramway, she was painted brown-orange with red bufferbeams and a white roof.
In the television series, Henrietta is painted brown-orange with red bufferbeams and a grey roof.
- Toby the Tram Engine - Toby and the Stout Gentleman, Thomas in Trouble (does not speak), Dirty Objects (does not speak) and Mrs. Kyndley's Christmas
- Gordon the Big Engine - Paint Pots and Queens (cameo)
- The Eight Famous Engines - Double Header (mentioned) and The Fat Controller's Engines (does not speak)
- Branch Line Engines - Daisy (not seen) and Percy's Predicament (does not speak)
- More About Thomas the Tank Engine - Thomas, Percy and the Coal (mentioned)
- Toby, Trucks and Trouble - Toby's Seaside Holiday (mentioned)
- Thomas Comes Home - Thomas Comes Home (cameo)
- Wilbert the Forest Engine - Wired-Up (cameo)
- Thomas and Victoria - Overloaded and Toby's Vintage Train (does not speak)
- Thomas's Christmas Party (does not speak)
- Thomas and the Missing Christmas Tree (cameo)
- Season 1 - Toby and the Stout Gentleman, Thomas in Trouble (does not speak), Dirty Objects (does not speak) and Thomas' Christmas Party (cameo)
- Season 2 - Daisy and Percy's Predicament (does not speak)
- Season 3 - Time for Trouble (does not speak) and Thomas and Percy's Christmas Adventure (does not speak)
- Season 4 - Thomas and the Special Letter (cameo) and Paint Pots and Queens (cameo)
- Season 5 - Toby's Discovery (does not speak), Sir Topham Hatt's Holiday (does not speak) and A Surprise for Percy (cameo)
- Season 6 - A Bad Day for Harold the Helicopter (cameo), The Fogman (does not speak), It's Only Snow (cameo), Percy's Chocolate Crunch (cameo) and Toby Had a Little Lamb (does not speak)
- Season 7 - Percy Gets it Right (cameo), Toby's Windmill (cameo) and Harold and the Flying Horse (cameo)
- Season 8 - James Gets a New Coat (deleted scene), You Can Do it, Toby! (cameo) and Too Hot for Thomas (cameo)
- Season 9 - Thomas and the Toy Shop (cameo), Thomas Tries His Best (cameo), Emily Knows Best (cameo) and Saving Edward (cameo)
- Season 10 - The Green Controller (cameo) and Toby's New Shed (does not speak)
- Season 11 - Thomas and the Lighthouse (cameo), Toby's Triumph (does not speak) and Thomas in Trouble (cameo)
- Season 12 - Toby's Special Surprise (does not speak) and Tram Trouble (cameo)
- Season 13 - Tickled Pink (cameo), Play Time (cameo), Toby's New Whistle (does not speak) and Splish Splash Splosh (cameo)
- Season 14 - Pingy Pongy Pick Up (cameo), Toby and the Whistling Woods (cameo) and O the Indignity (cameo)
- Season 15 - Toby and Bash (cameo), Happy Hiro (cameo), Let it Snow (cameo), Big Belle (cameo) and Tree Trouble (cameo)
- Season 16 - Flash Bang Wallop! (cameo), Bust My Buffers! (cameo) and Welcome Stafford (cameo)
- Season 17 - Gordon Runs Dry (cameo), The Lost Puff (cameo) and The Missing Christmas Decorations (cameo)
- Season 18 - Signals Crossed, Thomas the Quarry Engine, Spencer's VIP (cameo), Marion and the Dinosaurs (cameo) and Samson at Your Service (mentioned)
- Season 19 - The Truth About Toby, Den and Dart, Diesel's Ghostly Christmas (cameo), Two Wheels Good (cameo), Thomas the Babysitter, The Other Side of the Mountain (cameo) and Goodbye Fat Controller (cameo)
- Season 20 - Toby's New Friend, Letters to Santa (cameo), The Christmas Coffeepot, Three Steam Engines Gruff, Buckled Tracks and Bumpy Trucks, and Tit for Tat (cameo)
- Season 21 - P.A. Problems (cameo), Hasty Hannah, Philip's Number (cameo) and The Big Freeze (cameo)
- Thomas and the Magic Railroad (cameo)
- Calling All Engines! (cameo)
- The Great Discovery (music video cameo)
- Hero of the Rails (cameo)
- King of the Railway (cameo)
- Sodor's Legend of the Lost Treasure (cameo)
- The Great Race (cameo)
- Journey Beyond Sodor (cameo)
Learning Segments: Models:
- Season 8 - How Does Thomas Get to the Timber Yards? (cameo)
- Season 9 - Toby's Day Out (cameo)
- Season 10 - Toby's Favourite Place (cameo)
- Calling All Engines! - Which Diesel Engine with Which Steam Engine? (cameo)
- 1987 - Thomas' Christmas Party (cameo)
- 1988 - Toby and the Stout Gentleman, Thomas in Trouble, James and the Tar Wagons and Percy's Predicament (mentioned)
- 1989 - Showing Off and Clearing Up (mentioned)
- 1994 - Lucky Landing! (does not speak)
- 1996 - Duck and the Deer! (mentioned)
- 1997 - Toby's Castle (does not speak)
- 1998 - Toby and the Stout Gentleman! (mentioned)
- 2000 - A Shock for Mavis, Henrietta's Holiday and A Special Story About Henrietta
- 2001 - A Special Story About Toby (cameo)
- 2002 - Toby to the Rescue! (cameo)
- 2004 - Toby and the Lambs (does not speak) and Good as New (cameo)
- 2006 - First-class Carriage
- 2008 - Toby's Triumph (does not speak)
- 2010 - Toby Takes Over (does not speak) and Tram Trouble (does not speak)
- 2011 - Toby's Treat
- 2012 - Toby and Bash (cameo)
- 2013 - Henrietta's Holiday
- 2014 - Kite Flying (does not speak) and That's Snow Business
- 2015 - Signals Crossed, Toby and Bash (cameo) and Henrietta's Holiday
- 2017 - Den and Dart
Henrietta also appeared in the magazine story, The Poorly Engine!
- 1985 - The Strawberry Special (cameo)
- 1986 - You Never Know (does not speak)
- 1987 - Percy's Passengers (does not speak)
- 1992 - Percy and the Vicar's Prizes (mentioned)
- 1993 - Thomas and the Snow Block (does not speak)
- 1995 - Thank You, Thomas and Toby
- 1996 - The Wrong Shirt
- 1998 - Toby and the Mail Train (does not speak)
- 1999 - Toby Saves the Day (does not speak)
- 2000 - Thomas the Famous Engine
- Maggie Ollerenshaw (UK/US; eighteenth season onwards)
- Yumi Nakatani (Japan; first season only)
- Keiko Nemoto (Japan; eighteenth season onwards)
- Marta Dylewska (Poland; eighteenth season onwards)
- Talya Barkay (Israel)
- Isabel Romo (Latin America; eighteenth season onwards, excluding Thomas the Quarry Engine)
- Adriana Casas (Latin America; Thomas the Quarry Engine only)
- Layra Campos (Brazil; eighteenth season onwards)
- Laurence Sacquet (France and French speaking Canada)
- Margret Homeyer (Germany; Audio Book 4 only)
- Sabine Hahn (Germany; Audio Book 10 onwards)
- Despite not having a visible face until Thomas and Victoria (in the Railway Series) and the eighteenth season (in the television series), she had the ability to talk in the Railway Series books that took place before Thomas and Victoria, as well as the first, second and third seasons.
- One of Henrietta's models is currently on display in Japan at the Hara Model Railway Museum (previously on display at Nitrogen Studios).
- In an annual story, it was revealed that Henrietta has one surviving sister left, being a bogie version of herself.
- Throughout the model series, Henrietta's buffers were at different levels at either end.
- Henrietta went through several aesthetic changes in the television series:
- Season 6:
- Her running plate, which was only on her balconies, now runs from end to end.
- Her windows protruded out and the wooden ledge under the window disappeared.
- Her buffer beams slightly changed shape.
- Hero of the Rails:
- She increased in size to be the same height as Toby.
- The area under the side windows change from curving inwards to square and straight.
- Her step ladders slightly changed shape.
- Season 18:
- She gained a face at her back end. To accommodate this:
- Her door disappeared, she lost two of her four windows, and the remaining ones changed shape.
- The two vertical handrails disappeared.
- She gained square pillars on her corners.
- She gained a face at her back end. To accommodate this:
- Henrietta is one of three characters to have been given a face after a certain amount of seasons being without one, the other two being Big Mickey and Butch.
- Season 6:
- "It's not fair at all!" grumbled Henrietta as the buses roared past full of passengers. She remembers that she used to be full and nine trucks would rattle behind her. Now there are only three or four, for the farms and factories send their goods mostly by lorry.
- Henrietta, Toby and the Stout Gentleman, Toby the Tram Engine.
- Toby had wanted to take Henrietta, but the Fat Controller had said, "No!" He wondered if Henrietta was lonely. Percy had promised to look after her; but Toby couldn't help worrying. "Percy doesn't understand her like I do", he said.
- Toby and the Fat Controller, Double Header, The Eight Famous Engines.
Toby are we hiding?
Henrietta, Signals Crossed, The Eighteenth Season.
- ERTL (discontinued)
- Wooden Railway (discontinued)
- Motor Road and Rail (with Toby; discontinued outside Asia)
- TrackMaster (discontinued)
- Collectible Railway (coming soon)
- My First Thomas (discontinued)
- Trading Cards (discontinued)
- Thomas Engine Collection Series (discontinued)
- Mini Die Cast Collection (discontinued)
- Departing Now (discontinued)
- Thomas Town (discontinued)
- Pocket Fantasy (discontinued)
- Departing Now
- Capsule Plarail