Nia's wheel falls off whilst she's delivering a fish tank to the Vicarstown Fish Day event. When it's mended, she wants to make up for lost time and goes too fast with her precious cargo.
Thomas doesn't notice when Percy derails and tumbles down the side of a mountain. Thomas will have to put his knowledge of his best friend to the test in order to track him down.
While Bruno helps Diesel with a heavy delivery, Diesel fails to listen to his advice, causing them both to get stuck in Crumble Canyon. Now it's up to the two of them to listen to each other to find a way out and complete their delivery.
After Percy gets in an accident and ends up with a broken axle, Nia temporarily takes over his mail delivery duties for him and her mail delivery is even quicker.
Thomas and Percy are excited to deliver a special balloon for the hot-air balloon festival, but while making the delivery, part of the balloon pops out of its tarp and the wind carries it skyward, along with Percy.
Carly has developed a terrible squeak and Sandy finds an oil can to give her a feel-good surprise, but when she tries to make the fix bigger and bigger, she creates a wacky robot oil can squirter.
After a huge storm hits the Island of Sodor, all the power gets cut out. Thomas is tasked to deliver the generator all the way to Knapford Station without getting stuck when Gordon is unable to, but chooses to not get help from any of his friends.
Thomas and Percy explore a brand-new track the evening before the route is opened. Everything seems new and exciting, and even a night spent stuck in the mud turns into a wonderful experience.
When Percy is kidnapped by the stink monster, the members of the Biggest Adventure Club band together to come up with a plan to save their friend and stop the stink monster in its tracks.
After a storm causes a rockslide in Crumble Canyon, Ashima is eager to clean and clear the chaos with her new friends. However, Thomas and the others are concerned if Ashima were to help them, the mucky mess could ruin her beautiful paint.
When Diesel discovers that he doesn't just like to be known for his incredible strength, he finds an unlikely compatriot in Kenji who is tired of only being known for his swift speed.
On Plant-A-Tree Day on Sodor, Thomas and Diesel both want to deliver the most impressive pine for the holiday, but they'll have to compete by delivering all the other trees first.
When a new express tunnel opens in Sodor, both Thomas and Diesel want to be the first one through. However, their stubbornness might prevent them from enjoying the spring butterfly migration.
When Carly does not return from saving Emily from an accidental derailing, a worried Sandy recruits the help of a bored Diesel to find her best gal pal. The unlikely pair become detectives.
When he accidentally causes all the lamp posts in Vicarstown to fall and shatter, an embarrassed Sir Topham Hatt requests Thomas to go on a secret mission to Harwick for replacements in time for the evening concert
After yet another race, Kana seems unbeatable. No engine on the island is as fast as Kana. However, this does not stop Sandy from challenging Kana using her smarts and her small stature to her advantage
When a precious marble statue of his great-grandfather arrives, Sir Topham Hatt enlists the help of Thomas and Bruno in delivering it to Vicarstown Plaza
After Salty the Diesel Engine returns from his worldly travels, he sings a shanty to Thomas and Percy about a legendary treasure lost on the island of Sodor; the two friends are eager to see if the legend is true.
Thomas learns that the rocket he helped deliver is finally falling back to Earth into the ocean outside Sodor; Bulstrode, Carly and their team of retrieval experts are on the job to fish the rocket out of the water.
A rough night's sleep and a canceled beach day puts Thomas in the grumpiest of moods. Encountering Riff and Jiff with their usual happy-go-lucky attitudes, Thomas comes to the conclusion that he'll only be liked when he appears happy.
Thomas gets help from Terence and Carly to assemble hay bales; Terence purposefully crashes into the hay bales; they turn the hay-bale stacking into a game, forming all kinds of structures Terence can crash into.
When aging Toby comes to Knapford, he struggles to keep up with all the young engines. He still has a lot of zip in him, but around all these modern engines, he loses his confidence.
When water lines break all over Sodor, the engines chug into action to deliver repair parts. But engines are not what this problem needs, it needs off-track thinking and the help of Skiff and Terence
