Theodore the Big Red American Engine
Theodore is a big red Union Pacific Challenger Class 4-6-6-4 engine with blue wheels, blue lining and a blue cowcatcher from America, who is Hank's younger brother. He is so strong, he can pull over 100 trucks in one go without having an accident. He appears in the episode, "Big Brother Theodore". Thomas has to arrange his train, but Theodore gets called away, so Thomas decided to take his train. Unfortunately, the coupling between Thomas and the first truck breaks, and all 100 trucks derail into a really big heap. Thomas, his crew and the guard are alright though, but Thomas has to get help. He and Percy fetch Rocky, Jerome and Judy to clear up the mess. Hank and Theodore agree to help too. And most of the goods are undamaged, and 86 of the trucks are delivered safely to their destinations. Thomas, Percy, Hank and Theodore are now good friends.
Theodore is numbered 3985.
Theodore is named after the title character in Theodore Tugboat. So it is possible, Hank could have some connection to Theodore's best friend, Hank. It is also noticeable that Hank's livery is blue with red wheels, lining and cowcatcher, while Theodore's is vice-versa.
Theodore is voiced by Rob Rackstraw in both dubs.
Theodore's whistled sound is Murdoch's at a lower pitch.
Junichiro the Japanese Engine
Junichiro is Hiro's cousin, who once had an arguement with him many years ago before Hiro was brought to Sodor. After a quick reunion, they make it up to each other and become friends again.
Junichiro is named after Junichiro from King of the Hill.
Junichiro is voiced by Togo Igawa in both dubs.
Junichiro's whistle sound is Hiro's at a lower pitch.
Stavros the Greek Electric Engine
Stavros in a Greek engine based on the OSE Class 120 Engine, who was bought to attend the Shrove Tuesday Festival. He is painted blue and white stripes with a picture of a white cross in a blue box on his tanks, similar to the Greek flag.
Stavros is voiced by Jim Howick in both dubs.
Stavros' horn sound is Rusty's at a higher pitch.
Louie the Gray Dutch Diesel
Louie is a grey NS Class 6400 Diesel who joined the Thomas' Railway Band when the band went to the Netherlands.
Louie is voiced by Bob Golding in both dubs.
Quentin the Blue and White Canadian Diesel
Quentin is a blue and white EMD G12 Diesel who joined Thomas' band when they visited Canada.
Quentin is named Quentin Blake, the illustrator of the Roald Dahl books.
Quentin is voiced by Tim Whitnall in both dubs.
Bianca the Purple Hungarian Engine
Bianca is a purple MAV Class 424 engine (with white lining) who was invited to join Thomas's Railway Band during their visit to Hungary.
Bianca is named after Miss Bianca from Disney's The Rescuers not only by whom she is inspired by, but also on who her personality is based.
Bianca is voiced by Teresa Gallagher in both dubs.
Sonia the Argentian Engine
Sonia is a two-tone blue diesel (with red lining) from Argentina, who was a bit shy when she first came to Sodor. Because she was shy most of the engines were being mean to her, until she told the story of Vinnie's final moments to Salty, Paxton and Sidney. Then Thomas realised Sonia wasn't that bad after.
Sonia is named after Sonia the Hedgehog from Sonic Underground.
Sonia is voiced by Lucy Montgomery in both dubs.
Lionel, Grover and Jamie the GNR Engines
Lionel, Grover and Jamie anre the last three remaining of Ryan's Brothers. They hadn't seen Ryan ever since he arrived on Sodor until he invited them to spend Christmas for Molly's birthday.
Lionel is painted brown with a bushy moustache and eyebrows, Grover is painted blue and Jamie is painted green. Their numbers are 1011, 1012 and 1013 respectvely.
Lionel is named after Lionel the Helicopter from Budgie the Little Helicopter (whom his facial features are based on) and Grover is named after Grover Monster from Sesame Street.
Lionel is voiced by Jeremy Nicholas in both dubs, in the same voice he used for Lionel from Budgie, Grover is voiced by Tom Stourtion in both dubs and Jamie is voiced by Nigel Pilkington in both dubs.
Sebastian the Red Diesel
Sebastian is a friendly red diesel who is highly intelligent and smooth-talking. He proved this when he had to help Lionel, Grover and Shaun teach Jake, Horace and Lenny the big Mainland diesels some manners, after Ryan's brothers returned from the Mainland.
Sebastain is painted red with black lining. He is numbered 70017.
Sebastian is named after Sebsatian the Crab from Disney's The Little Mermaid.
Sebastian is voiced by Joe Mills in the UK dub and Christoper Ragland in the US dub.
Sebastian's horn is Diesel 10's at a higher pitch.
Zazu the Blue Narrow-Gauge Diesel
Zazu is a blue feisty, sometimes clumsy narrow-gauge diesel (with black lining) based on the Trecwn diesel. When he first arrived on Sodor, Sir Handel thought the trucks had told him to biff into all the engines on the Skarloey Railway. He was soon proven wrong when Zazu ran into trouble on a collapsing viaduct, and he had to save him. Now there are good friends.
Zazu is named after Zazu the Hornbill in Disney's The Lion King franchise.
Zazu is voiced by Clive Mantle in both dubs.
Zazu's horn sound is Derek's at a higher pitch.
Nicola the Green Minimum-Gauge Diesel
Naomi is a green minimum gauge diesel (with orange lining) based on Lady Wakefield. She and another diesel named Maurice were find by Mike in a scrapyard. Then Mike told the Small Controller who sent them to be fixed up, and then join the Arlesdale Railway.
Nicola is voiced by Nicola Stapleton (after whom she is voiced) in both dubs.
Maurice the Red Minimum-Gauge Diesel
Maurice is a red minimum gauge diesel (with white lining) based on Douglas Ferria. He and another diesel named Nicola were find by Mike in a scrapyard. Then Mike told the Small Controller who sent them to be fixed up, and then join the Arlesdale Railway.
Maurice is voiced by in Steven Kynman in the UK dub and David Menkin in the US dub.
Wilma and Betty the Bluebell Coaches
Wilma and Betty are a pair of optimistic and friendly Metropolitan Bluebell Coaches who were given to Stepney after he saved Gordon and Stafford from an accident oustide Knapford Station.
Their faces are the same look as the Slip Coaches, and they are painted in the Metropolitan Bluebell livery.
Wilma and Betty are named after Fred Flintstone and Barney Rubble's wives respectivley, from Hanna-Barbera's The Flintstones.
Wilma is voiced by Olivia Colman in both dubs, while Betty is voiced by Miranda Raison in both dubs.
Homer the Snowmobile
Homer is a brave purple and white snowmobile who likes to help out and rescue villagers in the winter. When he first arrives on Sodor, he has to rescue Salty from a snowdrift.
Homer is named after Homer Simpson, the title character from The Simpsons.
Homer is voiced by Darren Boyd in both dubs.
Rolf the Jetski
Rolf is a daring yellow and red jetski who likes to race very fast, especially on warm summer days. He normally gives water skiing events at the beach. When he first arrived, he challenged Captain to a race to the beach. They both won after Captain helped Rolf when he got stuck on a rock.
Rolf is named after Rolf from Ed, Edd N Eddy.
Rolf is voiced by Tom Stourton in both dubs.
Jasmine Hatt is Sir Topham Hatt's teenage grandniece, who is introduced in the special, "Thomas' ABC Story". She is also the older cousin of Stephen and Bridget Hatt, and she helps them learn their ABCs and 123s in "Thomas' 123 Story".
Jasmine Hatt in named after Princess Jasmine in Disney's Aladdin franchise.
Jasmine is voiced by Teresa Gallagher in both dubs.
Eleanor Hatt is Sir Topham and Lowham Hatt's auntie, Dowager Hatt's twin sister and Stephen, Bridget and Jasmine's great auntie. She first appears in the episode, "Christmas with the Hatt Family" where she is invited to Christmas lunch with a large number of humans, and a reunion with her sister, her twin nephews, her three grandchildren and the rest of the humans at the Christmas lunch.
Eleanor is voiced by Rebecca O'Mara in both dubs.
Matt the Mobile Shop Owner
Matt is the friendly owner of a mobile shop who makes his first appearance in "Thomas' ABC Story".
Matt is voiced by Matt Wilkinson (whom he is named after) in both dubs.
Bernie Harrison is Stephen and Bridget Hatt's teacher. who first appears physically in "Thomas' 123 Story". In this special and its prequel "Thomas' ABC Story", he assigns for Sir Topham Hatt's children to learn their alphabet and counting as soon as possible, the numbers 1-20 before Easter.
Mr. Harrison is voiced by Rob Rackstraw in both dubs.
Otto the Diver
Otto is a skilled driver who operates and owns Rolf. He is also a quick swimmer, as he knows almost at once, if anyone needs help in the water.
Otto is named after Otto Mann from The Simspons.
Otto is voiced by Bob Golding in both dubs.