Carry, the carrier car, drops Bongbong, the baby van, by mistake. Suddenly left all alone, Bongbong luckily runs into Tayo. They have fun together while Tayo teaches Bongbong about the traffic rules. Tayo takes a real liking to cute Bongbong and invites him to the garage. Meanwhile, Carry finally realizes that Bongbong is missing and goes to look for him. However, Bongbong and Carry keep missing each other.

Upon finding a bus stop covered in graffiti one day, Rookie and Pat decide to investigate. But conflict arises as Rookie wants to use cutting-edge technology while Pat insists they patrol on foot. Caught up in their argument, they lose the culprit. Unwilling to give up their respective methods of investigation, Rookie and Pat get into a huge fight, then decide to look for the culprit separately. Will Rookie and Pat be able to catch the culprit?

Gani stands in for Cito as a one-day teacher introducing what a bus does to kindergarten students. The heavy vehicles and cool cars like patrol car Pat and fire engine Frank all gather at the education center to participate as a one-day teacher. Gani becomes timid as he listens to the heavy vehicles, Pat, Frank, and Alice all introduce their jobs confidently. But after some encouragement from Hana, he decides to do his best. When it's Gani's ...

Tony is on his usual delivery route when he meets Tayo and gets invited to the garage. In his hurry to finish up his work and go play at the garage, Tony accidentlly delivers a child's toy to the wrong house. Big hears about this mistake from the child's father and tells Tony that he made a wrong delivery. Then he goes to deliver the toy himself instead of Tony. On his way back, Big gets stuck in a narrow road because of his big frame.

Nuri had been humiliated at a singing contest she entered with Speed at a taxi get-together. This time she decides to enter with Tayo who can sing well. Suddenly, Rogi imposes himself on them, saying he wants to go, too. But Nuri can't go to the get-together with Rogi who has a terrible singing voice. So Nuri makes up an excuse and starts to practice songs with Tayo. Rogi's pride is hurt, so he keeps on disrupting their practice sessions. Wil...

While on their route, Tayo and Rogi save the garbage truck, Rubby, from trouble. Later, they discover an old parking lot by chance and have such fun playing there that they return to the garage late. Tayo and Rogi are dirty from playing in the old and dusty parking lot. Hana and Cito scold them and tell them they are not allowed to play in the dirty old parking lot again. Incidentally, Rubby learns that Tayo and Rogi can't play in the old par...

By chance, Tayo saves Nana who was in trouble. Nana lives in the country and she's visiting the city. So when Tayo shows her around the city in a very skillful manner, Nana thinks that Tayo is the boss of the buses. Tayo feels good upon hearing someone call him, "boss," so he doesn't deny it, and then parts ways with Nana. But after Tayo gets back to the garage from his route, he sees Nana with the other little buses. Afraid that the others w...

All morning, Nuri encounters unfortunate events until eventually, she gets in an accident. While getting repaired, she learns that the little buses are going to ride a cruise ship today. Nuri wants to ride a cruise ship, too but becomes disappointed when she learns that there is no more space available. Hana gives Nuri a necklace as a gift to cheer her up. Nuri first doesn't believe it, but after she wears the lucky necklace, everything start...

One day, Tayo finds a treasure map in the storehouse. Greedy for the treasure, each of the little buses try to secretly find the treasure on their own. After pretending to go somewhere else, they each look for the treasure to no avail. They realize that they deceived one another and get into a fight. With Cito's advice, they find out where the treasure is buried. Everyone races toward the place where the treasure is supposedly hidden. When th...

One day, Lani accidentally breaks the car wash. Afraid she'll get scolded, she keeps it a secret. Meanwhile, Rogi declares he'll find the culprit who broke the car wash and, acting like a detective, starts asking the little buses a lot of questions. Lani can't answer Rogi's questions straight away and gets suspected of being the culprit. But with Tayo's help, she is able to leave the garage safe and sound. Seeing Tayo do that, Rogi starts to ...

One day, Rogi brags about the rubbish he's collected to the little buses. But the other little buses get angry at him because the rubbish is so dirty. The next day on his route, Rogi meets a camping car named Windy who has the same taste as he does. Rogi feels close to Windy who says that he travels the whole world freely, so he invites him to the garage. Meanwhile, the little buses who are now regretting getting angry at Rogi decide to apolo...

Accidents keep happening on the parking lot playground. So Hana decides to elect a playground leader to maintain order on the playground. Lani, Tony, and Speed are all vying for the position, and with Rubby somehow thrown into the mix, suddenly, there are four candidates who want to be the leader. The next day, the candidates start campaigning. Lani, Speed, and Tony have thoroughly prepared and delivered very polished speeches. However, Rubby...

Cito always helps the little buses, but he is also sometimes strict. The little buses feel a bit uncomfortable around Cito because he always looks like he knows what he's doing. They think Cito is an entirely different kind of being. Then one day, Booba, the grandfather bus who was Cito's predecessor, arrives. Seeing Cito become flustered in Booba's presence, the little buses are dumbfounded. Booba tells the little buses stories of Cito's chi...

The princess of a neighboring country visits Tayo's city, and upon seeing her, Lani desires to become a princess as well. Realizing that she can never become a princess, Lani starts to become ill. To cheer Lani up, Hana suggests that the little buses treat Lani like a princess for one day. The little buses start to treat her like a princess, being at her beck and call. But since the little buses are unaccustomed to Lani acting like a princess...

Tayo is envious of the grown-up buses who can drive around until late at night and can sleep in until late in the morning. By chance, Tayo helps a grandmother car, Wizard car who turns out to be a wizard. She says she'll grant him one wish. Tayo uses his wish to become a grown-up. Tayo is happy that he can now play until late at night. But the good feeling doesn't last long. Tayo realizes the responsibilities he must take on as a grown-up bus...

Hana invents the machine that can shrink anything. Hana strictly tells Tayo not to touch the machine, but Tayo, who is full of curiosity, touches the machine anyway and gets hit by a mysterious ray. The ray shrinks him into a tiny toy bus. Just then, Rookie and his niece, Jinnie, visit the garage. Jinnie, who's been carrying around a toy bus, thinks that Tayo is her toy bus and takes him home with her. Will Tayo be able to return to the garag...

On the day people say shooting stars will fall, Tayo thinks of Princess Ray of the Clover planet. That night, Tayo and the little buses wake to the sound of Princess Ray's voice calling them from afar. The little buses hear Princess Ray's request for help because she's been captured by Bully. So they decide to travel out into space to save her. The little buses blast off into space with the space rockets Hana made for them attached to their b...

Tayo infiltrates Bully's castle with Quick and finally meets Princess Ray. But when he's about to escape the prison with Princess Ray, the prison gates suddenly close and Tayo is now also trapped in the prison. It turns out that it was Quick's plan all along to capture Tayo and the little buses. Bully is now triumphant about catching Princess Ray and Tayo. Will Tayo and Princess Ray be able to escape Bully's prison?

As always, Speed and Shine once again wreck the downtown roads while racing each other at breakneck speed. Rookie and Pat become angry and order them to do something good and receive a stamp. Upon learning that if they can't get a stamp, then they'll be banned from the roads, Speed and Shine hastily agree to help their friends. But since they've never done anything good in their lives, they end up messing up their friends' work.

One day, Gani gives Jerry, the neighborhood's most reckless troublemaker, a ride. Because of Jerry's mischief, Gani finds himself in tough spots every day. While contemplating on how to stop Jerry, Gani turns on the TV installed on the bus. Joey's Magic Show is on, and Jerry becomes immersed in the program, stops his antics, and sits quietly. After that day, Jerry promises to sit quietly on the bus as long as Gani shows him the Magic Show. Be...

Air is a new rescue helicopter that has come to the fire station. Tayo is completely taken with Air after seeing him bravely save people and asks him to become friends. The other little buses hear about Air and hope they can become friends with him, too. They try to approach Air, but small misunderstandings make them dislike Air. Will Air and the little buses be able to become friends?

Rogi hears about Frank and Alice who are stressed out because of prank calls and vows to catch the culprit. He sets out as a self-appointed detective with Gani. The only lead is that the culprit has a deep male voice. With that clue, Rogi and Gani try to find the culprit. But Rogi once again makes preposterous deductions and reasonings. A few days later, Rogi and Gani find out where the prank calls were made thanks to Rookie, and they plan a ...

In the dead of the night, the heavy vehicles that were working at the old factory come to hear the story of the ghost car. All the heavy vehicles start to act like they're not bothered, saying there's no such thing as ghosts. But when they hear a ghost's cry from afar, they all run off in terror. The heavy vehicles that are now back at the garage feign illness because they don't want to go back to the factory. Tayo and Rogi become curious aft...

The little buses and Hana are invited to the countryside by Nana. There they meet new friends Ractor, Champ, and Coco. Everyone is having a good time except Nana's childhood friend Coco who's upset that Nana seems to be praising Tayo all the time. Tayo and the other buses agree to help Ractor with a few things, but when Tayo repeatedly makes mistakes, Coco jumps at the opportunity to criticize him. But Nana only comforts Tayo more, which make...