Plot

Thomas the Tank Engine searches for gold dust that will allow his magical friend Mr. Conductor to return home, while also helping a girl restore her grandfather's enchanted locomotive.

Mr. Conductor's supply of magic gold dust, which allows him to travel between Shining Time and Thomas's island, is critically low. Unfortunately, he doesn't know how to get more. Meanwhile, Thomas and his engine friends are fending off attacks by the nasty Diesel 10 and his goons. Getting more gold dust will require help from Mr. C's slacker cousin, his new friend Lilly, and her morose grandfather, plus the secret engine he's hidden all these years and couldn't get running.—Jon Reeves <jreeves@imdb.com>

An evil diesel locomotive called Diesel 10 has arrived on the Island of Sodor, with the intention of destroying the steam locomotives. His plan is to locate a magical lost engine and destroy her in order to remove the magic from the Island. Sir Topham Hatt, normally in charge of the railways on Sodor, is on holiday and has left Mr. Conductor in charge. Mr. Conductor has problems of his own. The mysterious gold dust that allows him to magically transport from place to place is running out, and without it there will be no way for anyone to travel to Sodor. The lost engine is able to travel between Sodor and Muffle Mountain via the Magic Railroad, but nobody knows where she is. An old man named Burnett Stone lives on Muffle Mountain, near Shining Time. Unknown to everyone, he is the guardian of the lost engine. The engine crashed after an earlier encounter with Diesel 10, and ever since then he has been trying to repair her, so far without success.—Anthony Pereyra {hypersonic91@yahoo.com}

The magical island of Sodor, the railway land of talking trains and vehicles, was once a realm of magic and innocence. but when the Fat Director of Sodor leaves for a holiday with is family, a force of evil diesels of the dark side arrive at the island of Sodor to cause great danger and peril to the engines and trains, and threatens to kill the engines and trains and find the magical secrets of Sodor to take over and rule Sodor forever. the world's greatest train, Thomas The Tank Engine along with his friends must go on a magical fantasy adventure quest to go and save Sodor from the evil diesels and find the magical secrets to restore the magic, solve the mysteries and save Sodor. Thomas soon learns that though he is still a small engine, he is capable of doing big heroic things.

The worlds of Shining Time Station and Sodor Island are about to become intertwined with each other: as Mr. Conductor's good dust supply is running low and needs to find its source before the nefarious Diesel 10 destroys the source of its power: The Steam Engine Lady. With Thomas the Tank Engine's help, Mr. Conductor needs to save not only his own world, but the Island of Sodor too.—Johnny-the-Film-Sentinel-2187

the movie takes place between the 5th and 6th seasons of the series, it also tells a backstory of a magical engine who ruled Sodor long ago until she was chased and crashed by diesel trains of the dark magic.

Thomas The Tank Engine is a small, blue, wise and brave tank engine train locomotive. he is also a cheeky little engine with six small wheels, a short stumpy bunker, a short stumpy funnel and a short stumpy dome. he lives in the magical Island Of Sodor, a land of talking trains and other living sentient railway vehicles. he is usually cheerful and a Really Useful Engine who is right on track with his work, although some of the bigger engines pick on him occasionally. one week when the Fat Director and owner of The Island of Sodor "Sir Brendan Topham Hatt III" leaves for a holiday with his family and his wife Mrs Lady Hatt, a dark force of large dark evil diesel trains named "Diesel Ten - a large brown evil warship diesel with a giant robot monstrous claw coming out of his back who is the older brother of Dievious Diesel and Sodor's ultimate archenemy" and his troublesome diesel minions "Iron Sidekick Splatter and Iron Diesel Dodge - 2 mischievously evil and troublesome diesel twin brothers, almost identical except that Splatter is brown and Dodge is green" arrive at the Island of Sodor to cause great danger and peril to the engines. they also threaten to kill the engines and find the mysterious legendary magical lost engine and all her magical railways and secrets and destroy her to take rule of Sodor forever.

meanwhile, far away in the real world across miles of oceans, Sir Topham Hatt has hired Mr Conductor, the train conductor of "Shining Time Station (a popular magical train station on the Indian Valley Railroadline)", to do his job while he's away. Mr Conductor travels by using a whistle fueled by magical golden teleportation fairy dust called "Gold Dust" which teleports him when it is blown, but he's facing a crisis at running a bit low on Gold Dust. he eventually manages to reach to Sodor where is picked up by Thomas. and Diesel 10 sneaks up to their sheds at night and attempts to destroy them, his attack causes a big smash though the walls and manages to knock down the scaffolding. luckily Mr Conductor wakes up though unfortunately realises that he doesn't have enough Gold Dust, but instead scares Diesel away by threatening to throw a big bag of sugar into his petrol tank. that night, Mr Conductor has a nightmare vision of the future and he realises that if he can't travel anymore, the diesels' dark magic will spread over Sodor and cause Sodor's magic to decease and eventually will cause an end to Sodor or even the entire universe itself. he suddenly realizes he needs to find more supply of Gold Dust to save Sodor, the fate of Sodor in his hands.

next morning, a resourceful young teenager girl named Lilliana "Lily" Stone who lives in the "Big City" goes off to stay with her grandfather, Grandpa Burnett Stone, who lives on a mountain near Shining Time called "Mount Muffle". William "Billy" Twofeathers, the driver of the Shining Time Express, arrives at the Big City Station. and Billy's intelligent pet dog Mutt, who senses danger from far away, convinces Lily to go on the wrong train as a plan to save Sodor and Shining Time by making her get on the Shining Time Express. she arrives at Shining Time Station, but the manager of Shining Time, Stacy Jones, takes her to Muffle Mountain.

back at Sodor, Mr Conductor remembers that his parents once told him to look at the windmill to find Gold Dust. but he loses his way 'cause he doesn't have enough Gold Dust. he calls his cousin, Junior Conductor, to come and help him at Sodor. then Mr Conductor goes around looking for the windmill when he's caught by Diesel 10 suddenly, and Diesel 10 takes him to the giant, steep, collapsing Sodor viaduct bridge. Diesel 10 hangs him over the edge of the viaduct by his claw and threatens to throw him in unless he reveals to him the location of the magic buffers, a pair of magical buffers which Mr Conductor used to get to Sodor. but luckily Mr Conductor manages to pull out a pair of wire-cutting scissors and slices in half one of his petrol wire hose pipes on his claw, causing some of his petrol to leak out. this shocks Diesel 10 so much that he accidentally flings Mr Conductor up, sending him flying across the Island of Sodor and landing at the windmill.

meanwhile back in the real world, Lily meets a young teenage local boy named Patch who works for Burnett and they have a horse ride to Shining Time Station where she meets Junior who's getting ready to go to Sodor. Lily goes with him and they arrive Sodor. they meet Thomas the tank engine who's pleased to see Lily and they become friends, but isn't pleased to see Junior because of having unpleasant memories of Junior putting party poppers down his funnel. Thomas takes them on a train ride across Sodor and they meet Mr Conductor, who just like Thomas, is pleased to see Lily and they become friends, but isn't pleased to see Junior. Junior foolishly climbs onto one of the windmill blades while Mr Conductor isn't looking, pretending it's a Ferris Wheel. the wind blows so hard that he flies across Sodor, landing on Diesel 10's roof.

that night, Splatter and Dodge find the magic buffers. Thomas' best friend and trusty sidekick, Percy The Small Engine, spies on the buffers and informs Thomas about the situation. after discussing it with Mr Conductor and considering that Lily is late for her grandfather. Thomas takes Lily on the magic railway back to Muffle Mountain where she finds Burnett and Patch again. but Thomas is left there where the wind blows so hard that the steep cliff-like ledge he's on collapses to smithereens and sends him sliding, rolling and tumbling down Muffle Mountain and falling into a magical hole through a portal where he returns to the magic railway again.

Lily meets Burnett again and explains to him that they need his help to save Sodor, so Burnett reveals to Lily that he owned Lady the lost magical engine all along and that she can't work properly due to a lack of coal. so they use some special Sodor coal to bring Lady back to life again and they all return to Sodor, meeting Thomas, Junior (who'd just narrowly survived being thrown by Diesel into a huge fiery furnace in the Sodor scrapyard) and Mr Conductor back at the Grotto Station. then Diesel 10 arrives and has a big railway train chase across Sodor with Lady and Thomas. but when they get to the viaduct bridge which has nearly collapsed 'cause the magic is fading away, Thomas and Lady who are light little engines, make it quickly, painlessly and safely across. but when Diesel tries to make it across who's way too overweight and is going way too fast, it collapses under his huge weight and plunges down from great height and has a huge train crash into a huge waste-boat's barge full of brown filthy slimy boiler sludge.

then back at the Grotto, they figure out the secret clue to the Gold Dust and Lily mixes magical railway shavings with water make more Gold Dust. they all return to Shining Time Station as Mr Conductor gives the railway to Junior, Lily gives the Gold Dust to Burnett, Sir Topham returns from his holiday and Thomas rides off into the sunset. Thomas realises that as the movie ends, though he is still a small engine, he is capable of doing big heroic things.