Mike is a small strong red engine who prefers goods trains to passengers. He is the youngest out of the original three Arlesdale Railway engines.
Mike was built by built by Clarkson of York in 1966 from a design which aimed to incorporate improvements on the Ravenglass and Eskdale Railway's River Esk, and like their River Mite, has succeeded. Mike is tough, robust and powerful. He is more sure-footed than Rex, but his performance is sometimes erratic
Mike worked on an unnamed line in England until 1967, at which time their line closed down and he, Rex and Bert, were sent to Sodor to work the Arlesdale Railway. Not long after arrival, Mike mocked Duck when the latter had trouble with his whistle making unusual noises, which lead to Rex telling Mike to lose his whistle. While pulling a passenger train, a stray cow had wandered onto the line and Mike whistled so loudly to make her move that his whistle flew off. This meant that his crew and passengers had to whistle for him. To make matters worse, there were no spare whistles for Mike so he was sent to the quarries for the rest of the day. Mike would soon come across some sheep on the line and complained about how silly they were, with Rex pointing out how useful they were with their wool.
Mike, along with the other small engines, were offered to be in a book about Duke if they behaved. When the rescue team found him, Mike brought tools to help him out of the shed.
In 1976, a few months after Jock came into service, Mike decided to pay the new engine back for all his cockiness. So, whilst double-heading a passenger train, Mike reduced steam after the Green, causing Jock to pull him and the passenger train alone. However, Mike's plan backfired when his injector failed on the return journey and Jock had to take him home. After being mended, Mike apologised to Jock.
When Marion meets the small railway engines for the first time, Mike took her belief that they were magical much less kindly than the other two. The following day when Thomas came up to Arlesburgh West, depressed about being sent to work on the new branch line as punishment for derailing the Express Coaches. Mike, along with the others, sang "Never Overlook a Little Engine" to cheer him up. However, this lead to Thomas becoming overly eager to be useful, which lead to him falling into Calles Cavern. At dusk that day, Mike was shunting ballast wagons onto the chute when Marion reappeared at their junction to make a wish; while Rex and Bert managed to escape unnoticed, Marion trapped Mike on the chute with her shovel and held on until she made her wish. Mike escaped at full speed when Marion let go, but this only strengthened Marion's belief. When Sailor John went through with The Pirate Ship two nights later, the three small engines shunted a train of ballast wagons off the chute in front of the ship to decrease its speed after hearing Thomas approaching the junction. The ship ran over most of the hoppers, but one got caught under the flatbed the ship was on, lifting its front bogey off the track and slowing it down as a result. A loose rope from the ship then got caught on Ryan's buffer and he was able to derail the slowing ship.
As in the Railway Series, Mike lost his whistle when he came across a cow, and his temper when he came across some sheep.
Mike can sometimes appear a little cunning and arrogant. He thinks he should be in charge of the other two engines, though neither of them really let him boss them around. Bert simply humours him, but Rex goes out of his way to tease Mike and wind him up, which is not very difficult. Mike much prefers pulling goods trains to passengers, unlike Gordon, as he considers goods much more straightforward and less likely to complain. He is proud of his strength and appears rather confident, but he would not be so easy to tease if he was not hiding at least a little insecurity. He can sometimes be a little argumentative and irritable, and it is common for him to overheat when he loses his temper.
Mike is painted red with blue and yellow lining. He has a brass dome, brass builder's plates on the sides of his cab, red nameplates with gold writing mounted on each side of his boiler and "ARLESDALE" written on the sides of his tender in yellow. According to Rex, Mike used to be painted green. In the Railway Series his wheels are black, but in the television series they are red.
- 2007 - Thomas' Giant Coloring Book
- 2008 - Thomas' Sticker Express
- 2015 - Pirate Treasure, Sodor's Legend of the Lost Treasure (does not speak), Sodor's Legend of the Lost Treasure: Sticker Activity Book, and Sodor's Legend of the Lost Treasure: The Movie Storybook (does not speak)
- 2018 - Character Encyclopedia
- Tim Whitnall (UK/US)
- Tomohiro Tsuboi (Japan; Sodor's Legend of the Lost Treasure onwards, excluding The Great Race)
- Kiyonobu Suzuki (Japan; The Great Race only)
- Waldemar Barwiński (Poland)
- Stan Limburg (The Netherlands)
- Sergio Gutiérrez Coto (Latin America; Sodor's Legend of the Lost Treasure only)
- Christian Strempler (Latin America; twentieth season onwards)
- Dor Srugo (Israel; Sodor's Legend of the Lost Treasure only)
- Gadi Levy (Israel; twentieth season onwards)
- Bjørn Eivind Aasland (Norway)
- Constantin von Westphalen (Germany)
- In Mike's trading card promo, he is depicted as a 4-8-2 along with Rex and Bert and is missing his front coupling hook.
- When Mike was introduced in the television series, he gained a brakepipe, a lamp above his smoke box, and his buffers became more oval-shaped.
- For unknown reasons, Mike's right-hand cab windows appear to be animated with gold frames rather than yellow ones - the same applies to the handrails at the back of his cab.
- Mike has the most merchandise out of every Arlesdale engine.