When Nolik offers to help Katya fix her broken electric piano, he discovers that there are two Fixies living in Katya's apartment, Tweak and Geek . Nolik convinces the twins that it is safe to reveal themselves to Katya.
Tweak and Geek convince Nolik and Simka to do some parachuting with them instead of going to Fixie School. Wondering why they have not shown up for class, Grandpus tracks them down and meets the twins for the first time.
Grandpus and Basiya's first meeting is rather tense when the two of them get into an accident as a result of a prank Tweak and Geek played with a hook on Grandpus' Fixieboard.
On their first day of Fixieschool, Tweak and Geek play a trick on the other Fixie kids who have not met them yet pretending that one of them is actually a copy made in Professor Eugenius' 3-D printer.
Katya, determined to stay up all night to meet the Tooth Fairy after losing a tooth, makes it difficult for both her Mom and Basiya to deliver her a gift.
Professor Eugenius ask Tweak and Geek to stop dancing in his laboratory because he thinks science and dancing don't mix. Tweak and Geek think Professor Eugenius actually doesn't know how to dance and they challenge him to prove otherwise.
The Fixie kids are really excited to have Fire take their pictures and edit them in his photo editing program until they see the results of his "artistic" choices.
Toola is in a terrible mood and Simka and Nolik try different ways to raise her spirits. Nothing seems to work until she discovers the joy of jumping on a trampoline.
Nolik, Fire and Digit notice Tweak and Geek acting very strangely, using words they have never heard before. Fire is convinced the twins are up to no good and must be stopped. Digit figures out that the twins are actually speaking in code.
Tweak and Geek find a gift they believe Basiya intends to give to her "favorite". But which of the twins does Basiya like most? Digit, Fire and Verda set up a competition to see which of the twins is the smartest, strongest, and prettiest.
Digit is going to check the ages of ancient bones in Eugenius' lab. When Tweak and Geek play a trick on Digit by building a creature from a different bones, Digit has trouble identifying what he is examining.
Eugenius creates a recycling machine. Nolik thinks the machine is just a trick and flies inside to investigate. Eugenius, Simka and Toola are soon frightened that Nolik got recycled into a shoe.
After learning that Digit got time off of school for making an invention, Geek and Tweak claim to invent a perpetual motion machine so they can get time off as well. Digit thinks it can't be real and they might be faking it.
Wanting to get their own pack-o-mats, Grandpus devises a test for Tweak and Geek to construct a miniature power plant. The winner will get the one pack-o-mat he has available.
When Tweak and Geek learn that Professor Eugenius has not congratulated Elisa on her PhD, they order flowers online, unaware of the money they are charging to the Professor's credit card.
When Nolik wishes Fixies had Santa Claus like humans do, Basiya and Grandpus plan to surprise him. But things get confusing when both Basiya and Grandpus arrive dressed up like Santa.
After agreeing to help Professor Eugenius test out his x-ray machine, Elisa is frightened when the x-ray of her hand seems to show gears inside. How could she know that the gears are just Tweak and Geek trying to take x-rays of themselves?
Tom Thomas is frustrated he missed getting a picture of a bird with his smart phone because he had to take off his gloves. Simka helps him make a pair of gloves that will work on a touch screen.
After having a lesson on energy conservation at Fixie School, Nolik tells Simka, Geek, and Tweak he can't do his chores today because he needs to save energy.
Nolik thinks everyone has forgotten his birthday. To make matters worse they all seem to be making fun of unfortunate mistakes he made in the past. Could everyone really have forgotten Nolik's special day?
Tom Thomas' mom asks him to throw away things he no longer needs in his cluttered room, but it proves very difficult for him because of all of the memories attached to them.
Tweak and Geek convince Nolik that shirts grow from cotton plants as a way to trick him into doing their chores. When Katya discovers their trick she has a plan to turn the tables.
Right after Digit repairs Katya's air conditioner, Tweak and Geek get into an argument about whether the room should be hotter or colder. Their argument leads not only to them breaking the unit's remote, but the air conditioner itself.
When Katya's Mom discovers a comic strip that Katya drew of Freak and Geek on her tablet, she wants to post it online to share with her followers, but this could expose the secret of the Fixies.
Digit and Nolik built a roller coaster that will be ready to ride after safety testing. Digit leaves to bring back equipment for the test and tells Nolik not to play with the roller coaster while he is gone, but it doesn't stop.
Nolik wants to play hide and seek with Simka, but Simka is more interested in studying math. Nolik tricks Simka into going to the kitchen and leaving her Fixietab with him. He hides it and forces his sister to play hide and seek.
Tweak and Geek get themselves covered with plaster that Elisa is using to make a bust of Professor Eugenius. When Elisa discovers the tiny plaster "models" she decides she will paint them. Tweak and Geek need to figure out how to escape.
Grandpus asks Simka to help Fire study for a math test. Fire discovers a cheat sheet Simka made with all of the formulas. Thinking that this is how Simka excels on her tests, Fire takes the cheat sheet to use on his test but gets caught.
Fire gets upset when Nolik goes wall climbing with Tweak and Geek. Fire sends Nolik photos of him climbing mountains to make him jealous. When Nolik figures out the photos are fake, he confronts Fire over a video call.
Katya's Mom is about to start her live stream, but discovers her headphones don't work. Tom Thomas offers to fix them, claiming to be a master repairman. He sneaks off for help from Tweak and Geek who discover the problem.
Tom Thomas gets a new hover board but doesn't know how to ride it, so Nolik offers to help. Not having any success, Tom Thomas tells Nolik he is a bad teacher leading to a fight between the two.
Tom Thomas gets a video call from Katya. She shows off her new sneakers that light up. Not wanting to be outdone, Tom Thomas tells Katya that he too has light-up sneakers and recruits Simka and Nolik to make Katya believe his fib.
When Tom Thomas tells Tweak and Geek that being a Fixie is so much easier than being a human, the twins create a virtual reality game in which Tom Thomas must travel through Katya's house as a tiny Fixie.
When Freak and Geek tell Grandpus they may be moving away forever with Basiya, Grandpus is distraught that he may never see Basiya again. Grandpus decides to build models of the most famous towers in the world to keep Basiya from moving.
Mom goes out shopping and asks Tom Thomas and his dad to mop the floors and dust the house while she's gone. But the two are soon distracted when Dad finds his old guitar and asks Tom Thomas to sing with him.
Fire is frustrated that Chewsocka continually interrupts a board game he is playing with Nolik. He sets up a hologram of food to distract Chewsocka. His contraption gets stuck on the poor dog's snout.
Katya's mom reads a beautiful weather forecast and suggests they go out for a walk. Determined to keep Katya from heading out, the Fixie twins hack into the station making Katya and her mom believe it is going to be a terrible day.
When Tweak and Geek hear Tom Thomas's mom speaking with a voice assistant, they think a new Fixie has moved into the house. But the twins are very confused by assistant's lack of desire to meet them.
Nolik really hopes that this year his Fixie family can celebrate Christmas in the freezer where they can play with snow, but Masiya doesn't like this idea at all.
Tom Thomas is upset because he had a fight with Katya, and now he is not invited to her birthday party. Nolik suggests that he just go to her and apologize, but Tom Thomas says that he doesn't have a birthday present.
Toola is upset that Fire and Nolik are playing an abusive game with a live plant. She explains that the plant is a Venus Flytrap and it can actually catch them if they are not careful.
Tom Thomas wants to ask Katya to go to the movies with him but doesn't have the courage to ask her directly. Nolik suggests he writes her an invitation and deliver it to her with his quad copter.
Masiya is worried that Nolik will get hurt swinging on a wire, and demands he gets down. Nolik refuses and actually falls. He doesn't hurt himself, but is still punished for misbehaving.
Tom Thomas is not excited at all when he receives the book "Treasure Island" as a gift from his grandmother. He thinks reading is boring. But Simka slowly manages to get Tom Thomas and Nolik wrapped up in the story.
Tom Thomas recruits Nolik to try and help him pass his spelling test with a sneaky plan: Nolik will tell him the answers through his wireless headphones. But things don't go as planned when Nolik has trouble communicating clearly.
Basiya teases Grandpus and brags that she has far more energy than him because of her exercise regime. Grandpus takes this as a challenge and the two have an exercise competition.
Papus and Nolik see Tom Thomas's Dad asking someone inside his new computer for help and they are convinced that one of their family members must be in the device. What they don't know is that Dad is getting help through the Internet.
