Robot heroes in training Elmo, Cookie Monster, and Abby Cadabby use their STEM superpowers to solve wacky larger-than-life problems.
When Marwyn runs out of ice, the Martians send a giant hunk of ice. All goes well until the ice starts sliding towards the skyscraper!
Zee's super sticky slime spills on Zee and MacBarm, leaving them stuck together.
The mysterious "Pretty Big Thing" is scaring the people of Pretty Big City from going to work… but what is it?
Izzy and Timmy go to dig up treasure at the top of Lawrence Pinecone's Statue's shadow… only to find that nothing's there!
MacBarm and Zee built a slide that sends people all the way across the farm… which means people spend more time walking than sliding.
The Martians want to help Lloyd deliver packages, but keep breaking them when they drop them from up high.
Marwyn attempts to make Pretty Big City's largest cookie, but to do so, he'll need a lot of help.
Zee's new drone accidentally doubles as a cow caller, and the cows keep leaving the farm to go see it. But how?
Timmy can't wait to trick or treat as a Mecha T-Rex, but his Halloween is almost ruined when he can't reach the arms to his costume.
It's Halloween and everything is set for the Zee Mobile to pull the haunted hayride… until it drives away.
Zee is showing off his inventions at his rocket-powered show, including his latest creation, a rocket powered Ferris wheel.
Panic erupts in Pretty Big City when the big clock breaks and no one is able to tell what time it is.
Zee needs to communicate with Sif in outer space but can't because a bird has made its home on top of the satellite dish!
The Martians come to Pretty Big City but find themselves in need of help when they are unable to land their spaceship.
Ranger Nat is bringing a playhouse on the train for Timmy and Izzy, but it won't fit through the tunnel!
It's MacBarm's day off and Zee takes over harvesting carrots with his Zee mobile, but when it breaks, the work still needs to be done.
Zee makes a giant rocket ship in a bottle, but things take a turn when he gets stuck inside!
Lloyd is selling silly hats at the factory, but when the hat machine malfunctions it starts raining silly hats on Pretty Big City!
Sif's coming in for a landing at the rocket launch site - until her rocket is pushed off course by a satellite!
Lloyd's testing a wind-up powered go-cart, but a problem arises when it keeps running out of energy.
It's time for Zee and MacBarm's gift exchange, but the snowman scarecrow Zee made for MacBarm keeps blowing away!
When the ornaments on the Pretty Big City tree break, the Mechas must build new ones and save the holidays for their friends.
Ranger Nat is hiking and comes across the Big-Footed Cave Bird, and realizes it can't get back into her home.
Grandma and Timmy are entering the Pinecone Art Show by carving a sculpture out of stone… that is, if they can learn how to carve.
The Zee Mobile is great at counting the chickens at the farm, but won't stop crashing into and ruining MacBarm's barn door.
The train needs to cross the ravine, which becomes difficult when the Martians accidentally break the bridge.
After Ranger Nat's kite blows away in the wind, the Mechas and Timmy learn to build their own kite to find it.
Zee's growth ray turns Moobert giant, but when a storm rolls in, the Mechas need to build a shelter big enough to fit her.
It's the opening day of the skyscraper and the Mechas need to put the sphere on top of the building before the ribbon cutting ceremony.
It's MacBarm's croquet tournament and Zee made giant decorations but they're too big to get to the farm.
Gerry and Nat are leading the Treetop Troops on a hike, but Nat finds himself lost in the woods as it gets darker.
Berta is opening an exhibit on the Whatsacallit of Treetop Woods. If only she could get a picture to prove it's real.
Grandma and her twin sister want to recreate their old zipline act, but quickly discover that the zipline no longer exists!
MacBarm is bringing food to his hungry chickens, that is, until all of the food falls out of his truck.
Izzy and Timmy are making a bird caller for Grandma, but have trouble connecting pieces of their machine.
The windmill isn't turning, which means Sunny Field Farm has no power. The windmill needs to turn again so Zee can launch his rocket!
Zee and MacBarm are setting up their corn maze with the help of Zee's Zee Mobile... that is, until it breaks down inside the maze.
Ranger Nat's hike turns to adventure when he finds a treasure map. The only problem is that he can't read it.
Pretty Big City finds itself in a sticky situation when the factory starts spewing super sticky slime everywhere!
It's the Pretty Big All City Read and Izzy and Barb are ready, that is, until all the books go missing!
Ranger Nat can't wait to see Pinecone's Comet, that is, until his telescope falls to the bottom of a cliff.
Farmer MacBarm is hosting the Sunny Field Farm Chicken Roll, but the race gets off to a slow start when the chickens don't roll.
Pretty Big City is cooling off with an ice slide in the park, but the situation gets slippery when the slide starts melting.
Hero Celebration Day is finishing with a slideshow of everyday heroes, that is, until the projector screen rips.
Roof is delivering eggs to Marwyn at the Train Station, that is, until the train pulls into the station and can't stop!
The magnet crane at the construction site accidentally turns on, sucking up all the metal, including the Mecha Builders!
It's Food Day in Pretty Big City, but the Mechas need to help when the banana atop the banana split statue is not split!
When Big Old Boulder rolls down the hill towards the museum, Berta needs the Mechas help to keep it stable.
Zee is ready to launch his rocket into space, but when the launchpad breaks, the rocket is launched into the farm instead.
Ranger Nat is stuck at the bottom of the crevice, but the problem grows when Mecha Abby also gets stuck.
The Singing Stone Heads are ready to perform at the Museum, but when they open their mouths, they sneeze instead of sing!
A giant pie is sent to Pretty Big City to stop an asteroid… but the Mechas and friends have eaten the whole thing!
Robot heroes in training Elmo, Cookie Monster, and Abby Cadabby use their STEM superpowers to solve wacky larger-than-life problems.
Ryan Dillon , David Rudman , Leslie Carrara-Rudolph
Sesame Workshop , Guru Animation Studio
as Mecha Elmo (voice)
as Mecha Cookie Monster (voice)
as Mecha Abby Cadabby (voice)
