The eighth season of the television series was the first to be produced by HiT Entertainment. The twenty-six episode season was first broadcast in 2004 and narrated by Michael Angelis in the UK and Michael Brandon in the US.
- Thomas and the Tuba - Thomas looks for the brass band's tuba player.
- Percy's New Whistle - Percy plays pranks with his whistle.
- Thomas to the Rescue - Diesel gives Thomas a hard time.
- Henry and the Wishing Tree - Henry learns to be careful what you wish for.
- James Gets a New Coat - James learns that pride comes before a fall.
- Thomas Saves the Day - Thomas tries to tackle a dangerous bend without Annie and Clarabel's assistance.
- Percy's Big Mistake - Percy is frightened he will be sent to the Scrapyards.
- Thomas, Emily and the Snowplough - Thomas ignores Emily's advice.
- Don't Tell Thomas - The engines are organising a party for Thomas but are not sharing the secret with him.
- Emily's New Route - Emily thinks there is a monster in Castle Loch, and tries to find another way round.
- Thomas and the Firework Display - Thomas helps James deliver the fireworks before the display is called off.
- Gordon Takes Charge - Gordon shows off to Percy.
- Spic and Span - Thomas and Percy try to beat the big engines in a cleanliness competition.
- Edward the Great - Edward races Spencer to The Duke and Duchess of Boxford's Summer House.
- Squeak, Rattle and Roll - Gordon tries to go slow so his squeaking and rattling won't be heard.
- Thomas and the Circus - Thomas tries to pull the circus train all by himself.
- Thomas Gets It Right - Thomas gets competitive about his deliveries.
- As Good as Gordon - Emily gets to pull the Express and tries to do the job as good as Gordon.
- Fish - Thomas gets into bother on Arthur's coastal branch with a long line of trucks.
- Emily's Adventure - Emily learns to use her manners after a storm has hit Sodor.
- Halloween - Emily accidentally scares herself as well as Thomas, 'Arry, and Bert.
- You Can Do it, Toby! - Toby gets nervous when he has to look after Wellsworth.
- Chickens to School - Lack of sleep gets the better of Thomas.
- Too Hot for Thomas - Thomas has to deliver ice cream ingredients.
- James Goes Too Far - James refuses to help his friends when he is given a very important job.
- Percy and the Magic Carpet - Percy is disappointed about delivering a carpet until Salty suggests that it could be magic.
- 'Arry and Bert
- Annie and Clarabel
- Sir Topham Hatt
- Farmer McColl
- Sodor Brass Band
- Murdoch (does not speak)
- Trevor (does not speak)
- Kuffy (does not speak)
- Lady Hatt (does not speak)
- Alicia Botti (does not speak)
- The Duke and Duchess of Boxford (do not speak)
- Henrietta (cameo)
- George (cameo)
- Caroline (cameo)
- Butch (cameo)
- Tiger Moth (cameo)
- Stephen Hatt (cameo)
- Bridget Hatt (cameo)
- Jem Cole (cameo)
- Farmer Trotter (cameo)
- Cyril the Fogman (cameo)
- The Refreshment Lady (cameo)
- Mrs. Kyndley (cameo)
- Nancy (cameo)
- Duck (music video cameo)
- Oliver (music video cameo)
- Toad (music video cameo)
- Rheneas (music video cameo)
- Rusty (music video cameo)
- Jeremiah Jobling (music video cameo)
- Donald and Douglas (deleted scene, mentioned)
- Bill and Ben (deleted scene)
- This is the first and only season to date that did not introduce any new non-human characters.
- This was the first season not to have Britt Allcroft and David Mitton involved in production.
- This was the first season not to feature the Skarloey Railway since its debut, although Rusty and Rheneas made stock footage cameos in a song.
- This season was the first to use the new opening titles and theme.
- The original opening is used in the Greek version.
- CiTV had a special opening theme when they broadcasted this season. This theme was also used on some US DVD releases. Also this was the last season to be broadcast on ITV, however this season did continue to be shown on CiTV until the end of 2007.