The Great Discovery is a feature-length direct-to-DVD special.
The railway is preparing for Sodor Day and Thomas and James are racing to the wharf to be given a special job by Mr. Percival. Thomas wins and is sent into the hills to collect lumber with Duncan. After Thomas teases Duncan, Duncan pays Thomas out by sending him on an old, disused line which he claims will lead Thomas back to the wharf faster. After avoiding an old, collapsing bridge, Thomas takes another route at the old junction, and as he journeys further down the line, he comes across an old overgrown town.
The news of Thomas' discovery spreads, and eventually reaches the Fat Controller, who tells Thomas that the town is Great Waterton - the largest town on Sodor when steam engines first came to the island. The Fat Controller decides that the restoration of the legendary lost town would be perfect for Sodor Day and calls the Pack to help. Thomas is told to take charge of the engines working around the town, while a new tank engine named Stanley is brought to do Thomas' regular jobs.
All of the engines take to Stanley, who does a good job and has fun as well, but when Thomas sees Stanley doing his jobs and fraternising with his friends, he becomes jealous. Thomas is furious when Stanley takes his place at Tidmouth Sheds, and the final straw comes when Stanley takes his place as the leader of the restoration project after Thomas has an accident.
Later, Thomas is shunting stone trucks for Stanley to take away when he decides to make Stanley look foolish by giving him a train too heavy for him to pull, but the plan backfires - as Stanley ascends the hill, a coupling breaks and the trucks race down the hill, veering into a siding, and crashing into the newly finished tower. The Fat Controller states that this will likely set back the restoration past Sodor Day, and Thomas is blamed. Stanley, however, realises that Thomas merely missed his friends, and wants to set things right.
That night, Thomas decides to clear the rubble out of the way. He is almost finished when he accidentally bumps a truck into an old mine shaft. Racing in after it, Thomas crashes onto a wooden platform and floats down an underground waterway. The engines soon realise that Thomas is missing, and the Fat Controller organises a search effort. Meanwhile, Thomas continues floating until he reaches an opening to the mine, and is flung across a canyon and down a hill.
Stanley decides to make another search effort by himself before he returns to work. Thomas, with the last of his steam, sounds a loud, long whistle. Stanley hears it and hurries to where Thomas is stranded beside the track. The two make up for their quarrel and Stanley pulls Thomas back onto the rails, but the strain is too much for Stanley and a valve bursts. Thomas, using some of Stanley's coal, pushes him back to Great Waterton. The word soon spreads that Thomas has been found.
The standpipe is rebuilt, completing the restoration. As a sign of friendship, Thomas offers Stanley his last job - bringing the mayor to the festivities at Great Waterton. The engines gather at the town for the celebration and Thomas realizes just how important his friends are.
- Sir Handel
- Mighty Mac
- Sir Topham Hatt
- Lady Hatt
- Miss Jenny
- Mr. Percival
- Bill and Ben (do not speak)
- Molly (does not speak)
- Mavis (does not speak)
- Salty (does not speak)
- Annie and Clarabel (do not speak)
- Rocky (does not speak)
- Terence (does not speak)
- Bertie (does not speak)
- Trevor (does not speak)
- Max and Monty (do not speak)
- Oliver (does not speak)
- Ned (does not speak)
- Jeremy (does not speak)
- The Mayor of Sodor (does not speak)
- Rosie (cameo)
- Whiff (cameo)
- Diesel (cameo)
- 'Arry and Bert (cameo)
- Diesel 10 (cameo)
- Dennis (cameo)
- Peter Sam (cameo)
- Rusty (cameo)
- George (cameo)
- Butch (cameo)
- Elizabeth (cameo)
- Buster (cameo)
- Stephen Hatt (cameo)
- Bridget Hatt (cameo)
- Jem Cole (cameo)
- The Refreshment Lady (cameo)
- Cyril the Fogman (cameo)
- Lord Callan (cameo)
- Sodor Brass Band (cameo)
- The Storyteller (cameo)
- Kuffy the Clown (cameo)
- Henrietta (music video cameo)
- Kelly (music video cameo)
- Great Waterton
- The Wharf
- Brendam Docks
- Sodor Shipping Company
- Transfer Yards
- Rolling River Bridge
- Village Square
- Knapford Yards
- Sodor Airport
- The Windmill
- Gordon's Hill
- Centre Island Quarry
- Dingley Hall
- Great Waterton Sheds
- Tidmouth Sheds
- Kirk Ronan Junction
- Morgan's Mine
- The Depot
- Henry's Tunnel
- Stepney's Branch Line
- The Great Discovery was shown in select theaters in the US
throughout July, in the UK throughout September, and in Australia throughout November of 2008. It made a return to Australian theaters on January 17th, 2013.
- Big Mickey and Vienna from TUGS can be seen.
- The last special to date here the US and the UK have the same narrator.
- The final Thomas and Friends production to be made at Shepperton Studios.
- This was the first for several things:
- The first special to be written by Sharon Miller.
- The first US DVD to be released by Lionsgate.
- The first special to be filmed digitally in high definition.
- This was the only time special for several things:
- Jamie Thomason's only special as voice director
- Pierce Brosnan's only special as narrator.
- The only special in which Diesel 10 appears, but does not speak.
- Diesel 10 and Butch's last appearances until Misty Island Rescue
- Arthur's last speaking role to date.
- Alfie's last speaking role until Sodor's Legend of the Lost Treasure.
- Harvey's last speaking speaking role until Gone Fishing.
- The last time Max and Monty are seen together until Sodor's Legend of the Lost Treasure.
- Terence's last appearance until Terence Breaks the Ice.
- Oliver's last appearance until Sodor's Legend of the Lost Treasure.
- Molly, Elizabeth, Madge, George, Dennis, Ned, Kelly, and Buster's last appearances to date.
- Stock footage from various eleventh season episodes is used.
- Pierce Brosnan
was to take over as narrator starting with this special. However, he departed the series after the special for unknown reasons, and was later credited as a "special guest narrator". Michael Angelis and Michael Brandon returned to replace him for the twelfth season to the sixteenth.
- Before Pierce Brosnan would take the role as the special guest narrator, Gwyneth Paltrow was in talks with HiT Entertainment according to SiF, thus would have made her the first woman storyteller for the series, however she immediately left.
- In the original US trailer, Fox was originally going to distribute the DVD.
- Among other things, the Sodor Daily newspaper reports that
"Percy is in tears", and mentions something about "Trevor the Traction Engine". Another article reports on an Alicia Botti concert. The paper's articles are apparently written by "J. K. Lee". The date for the newspaper is Monday, March 24th, 1955.
- This special was broadcast on PBS Kids Sprout on June 5th and 6th, 2010, and on ABC2 in Australia on April 24th, 2011.
- Special Walmart editions, including a bonus CD featuring all five songs from the special, were released.
- This special takes place between the eleventh and twelfth seasons.
- The first UK trailer was narrated by Tim Whitnall, who later joined the voice cast in 2014.
- Due to Jack and the Sodor Construction Company
never being shown in Norway, Japan, Greece, Poland, Finland and Romania, those viewers would not have known who Monty and Buster are.
- According to a behind-the-scenes photo, there aren't any rails on the bridge that Molly and Rosie are on.
- When Thomas and James race to the Wharf, the number of lines between them changes.
- When Thomas and James enter the wharf, Freddie and Skarloey appear twice in two different places.
- Stanley's siderods are out of alignment when his wheels spin as he struggles with the trucks.
- When the engines are shown covered in brick dust, Toby's face looks crooked.
- When Stanley returns to Great Waterton after the accident he
is on the track to Thomas' left. In the next scene, when Thomas is alone in a siding, Stanley is on the track to Thomas' right.
- When Stanley leaves Great Waterton to look for Thomas, James
is seen at the back of the group of engines. After Stanley realises that Thomas has been feeling upset, James is seen behind the line of stone trucks.
- When Thomas sees the barrier in the disused mine he brakes, but before he smashes through the barrier his wheels move.
- When Thomas falls off the bank the planks of wood that also fall are bigger than him.
- When Thomas tips over, a bent piece of rail used to push him up and off the rails can clearly be seen.
- When Thomas comes to a stop at the bottom of the hill, the
grass goes over his face, but in every following scene, the amount covering his face is different.
- After Stanley pulls Thomas onto the tracks, the points that
lead to where Thomas landed can be seen; this proves a hidden track was used to help Thomas onto the line.
- After Thomas is pulled back onto the rails, he becomes clean.
- As the events of this special take place in 1955, the appearances of several characters are anachronistic.
- Salty's basis was not built for another seven years.
- Diesel 10's basis was not built for another three years.
- Madge's basis was not built for another nine years.
- Max and Monty's basis was not around for another four years.
- Jeremy's basis would not have been built for another eight years.
- Emily would have to arrived sometime after 1967, as Oliver, who she saved on her first day, arrived that year.
- Rheneas was also away for repairs at that time and didn't come back until 1961.
- Peter Sam had not acquired his special funnel until that same year.
- Rusty and Duncan had not joined the Skarloey Railway until 1957 and 1958 respectively.
- Mavis was not loaned to Sodor until 1972.
- Diesel would not have visited Sodor until 1957.
- At the opening of Great Waterton, Gordon and Henry swap places twice by the standpipe, and Jack is sitting on the rails.
- Jack and Bertie have Caroline's horn sound.
- When Stanley pulls Thomas back on the tracks, a thin wire is seen pulling Stanley.
- On the UK DVD, in the game "Follow the Whistle", Gordon is in Edward's place.
- The narrator said that Sir Topham Hatt and Miss Jenny arrived
after the tower fell down, but Sir Topham Hatt is already at Great Waterton when the trucks rolled down the hill.
- Madge's eyes are wonky when she first starts talking to Mighty Mac.
- Some US trailers state that Thomas goes on a dangerous mission but he does not do so in the special.
- Thomas and James are Racing
- There's a Job for Everyone
- Where, oh Where is Thomas?
- Engine Rollcall
- Thomas, You're the Leader
DVD Bonus features Edit
- Introducing Stanley text
- Thomas and James are Racing sing-a-long
- Jobs-a-Plenty sing-a-long
- Where, oh Where is Thomas? sing-a-long
- Thomas, You're the Leader sing-a-long
- Follow the Whistle game
- Thomas, You're the Leader sing-a-long
- Behind the Scenes with Pierce Brosnan
- Spot the Difference
- Tough Trucks!
- Thomas' Puzzle Parts