Mavis was sent to Anopha Quarry to Shunt Trucks. Toby The Tram Engine was not pleased when Mavis started rearranging trucks in different places: Mavis was pleased when Toby said to arrange stuff herself. She talked to Diesel and told him she was not pleased with Toby, But Mavis Soon Learnt Her Lesson.
Percy The Small Engine once Puffed into Anopha Quarry, Mavis had not been pleased with Toby. However, Percy did not agree with Mavis' explain about Toby, Mavis decided to play a trick on Toby. She decided to shunt a train of trucks filled with piles of stones: Toby took the train arriving back at Anopha Quarry. But the trucks pushed him on and on and pushed him on a "tightrope", but Mavis proved to be useful pulling Toby back to safety!
Once, Salty the dockyard diesel was sent to work at Anopha Quarry. Bill and Ben were not pleased about Salty and his knowing how to Shunt Trucks, Bill and Ben Tried Doing it The same way: But They never did. The Trucks would never Pull Back or forth, However, Mavis was Pleased with Salty's visit. But later, Salty had been Pleased when Sir Topham Hatt Said He could go work at Brendam Docks again.
Bill and Ben often enjoy working at Anopha Quarry along with Mavis, But once Ben was going to get new shiny buffers because his old buffers broke: Bill, however, was not pleased because he wanted new buffers, too! Bill was so cross that he covered Mavis all in soot! But later, Bill crashed into some buffers slithering into a ditch. Ben later rescued Bill with the Breakdown Train and Ben apologized.
When Fergus The Traction Engine was sent to work at Anopha Quarry, Bill and Ben were not pleased at all. The Twins were also aggravated by Fergus' "do it right" attitude: they were soon sent to Brendam Docks to Collect a rock crusher. Fergus warned them But Bill and Ben took no notice and ignored Fergus' Warning and Made as much noise with the rock crusher as they could! Fergus Pushed The Twins out of The way just in Time! It Did take a Long Time to Dig Fergus out But Fergus was soon out!
Mavis is a feisty, young Diesel Shunter Working at The Sodor Slate Quarry. She Has four Wheels Hidden Behind her sideplates Like Toby's: She is feisty and can Be found rearranging Stuff. But Proves To Be Useful at Times.
- Season 1: The Trouble With Trucks, Stepney's Problem, A Scottish Tale (cameo), Lorry Takes A Tumble (cameo), Duties of The Diesels (cameo), Wilbert to the Rescue (cameo), Wilbert and Tigermoth (cameo), Frank and the Trucks (cameo), Wilbert, Frank, and the Milk
- Season 2: James' Tender Trouble, A Flying Surprise (cameo) and Disaster on Sodor
- Season 4: Naughty Engines
- Season 6: The Loose Caboose (does not speak) and Rosie Being Lazy
- Season 7: The Final Fate of Spamcan and Stanley, Whiff, and The Troublesome Dumptrucks
- Season 8: Tick-Tock-Jock, Frank and the Fib and The Almighty Alfie
- Season 9: Mavis and the Sleepy Engines
- Season 10: Scruff and S.C. Ruffey and Coal Crisis
- Season 11: Stepney and the Bluebell Branchline (cameo), Big City Rumor, Station Situation (cameo), Just Duck's Luck, Trembling Trevor (cameo) and BoCo and the Cocoa (cameo)
- Season 12: Stafford's Electric Slide, The Mavis Matrix and Rheneas and the Risky Rendezvous
- Season 13: Duck and the Quack Attack (cameo), Sam I Am (cameo) and Hector and Logan's Hot Pursuit
- Season 14: Freddie at the Ready (cameo), Dirty 'Arry (does not speak) and James in a Jam (cameo)
- Season 15: Roundhouse Roulette (cameo), Polar Express Coming Through! (cameo), The Island of Misfits Engines (cameo)
- Season 16: Marion Had a Little Lamb (cameo) Painting the Rosie's Red (cameo), Ace in the Hole (cameo)
- Season 17: Unidentified Flying Scotsman, Big Trouble on the Little Western (cameo)
Mavis is a Class 04 Diesel Shunter.