A day at the library turns into a cyberventure when Jackie, Matt, and Inez learn that Hacker has kidnapped Dr. Marbles, the only person who can save Motherboard from an evil virus. The rescuers learn to use a map as a mathematical tool as they navigate across a cyber island in search of Marbles—then try to escape before a huge earthquake turns the island inside out.

Cybersquad must stop Hacker from activating his newest creation, Gigabyte, before the light of the midnight moon, or else Dr. Marbles mind will be transferred into the monster, and Hacker will learn about all of Motherboard's secrets. The kids and Digit know Hacker is in a castle on a spooky, Halloweenish site called Castleblanca. Unfortunately, Motherboard wasn't able to specify which castle he is in. The kids must survey the residents of Castleblanca to pinpoint the exact location where Dr. Marbles is being held captive.

Digit is lured to R-Fair City, a cybersite full of carnival games, where he is kidnapped by a disguised Hacker. The kids must find the unfair/crooked game to find Digit. Meanwhile, they learn about chance and how to spot an unfair chance of winning and losing. Along the way they meet Lucky, a cab driver, who offers them a chance to gain a free cab ride while they search for Digit. Digit is locked in a bird cage with Buzz and Delete as his guards.

Hacker is looking for an eternal power source, so he steals Solaria's Sunisphere. The Cybersquad has to get it back before the whole site freezes over.

Hacker participates in a land rush in which participants cannot build property bigger than Judge Trudy's land. Hacker's land is accused of being bigger than Trudy's, but they turns out to be the exact same size.

The kids fail to stop Hacker from stealing Pandora's box in Mount Olympus, so they must solve a riddle and complete challenges to satisfy Zeus and earn a second chance.

Hacker attempts to take power from the vault in Poddleville for himself by stealing the residents' power pods, much to the detriment of the community. Each power pod has a shape and a number from 1 to 12, and after Inez and Matt are imprisoned it becomes a race to solve the pattern and enter the vault.

Wicked casts a spell that erases the memories of the citizens, so that they forget how to count.

Dr. Marbles finds the encryptor chip in an ancient pyramid, but the Mummy who guards the pyramid finds Marbles. When the Cybersquad arrives, they must work their way through the chambers of the pyramid, find Dr. Marbles, and escape before a trap set by the Mummy seals them inside forever.

Dr. Marbles builds Symmetria because of his passion of symmetry, but Hacker steals the symmetrizer and destroys Symmetria by splitting everything symmetrical in half. The Cybersquad has to figure out how to get the symmetrizer back from Hacker.

The kids are assigned to steal a crystal that powers Hacker's gadgets, while distracting Hacker with a series of spa treatments.

Hacker decides he needs to change his luck from bad to good, so he hires Baskerville, a new henchman, to replace Buzz and Delete while the 10 good luck charms of Cyberspace ensure him good luck. The kids and Digit use logic to rescue the charms and stop Hacker.

Professor Archimedes has the encryptor chip, but has to activate the emergency defense system when Hacker arrives to steal it. He and his building shrink to 2D, and the kids and Digit have to put him back to 3D.

Motherboard is suddenly sickened by the green liquid because of Buzz and Delete. So it's up to Digit and the kids to heal her using blue liquid.

Hacker challenges the kids and Digit to a game show entitled "Find Those Gleamers!", Gleamers being lightning bugs that power ships such as the Grim Wreaker. The kids have to make their ship, the Grim Wreaker 2, take off before time expires.

Hacker steals the cyber slug Icky to destroy Aquari-yum, and the kids make a code to fool him.

Hacker steals all the water from Sensible Flats to buy up their land, and the kids must determine when this started and how to fix it.

After Hacker kidnaps the kids, he crash-lands in Shangri-La, where Master Pi challenges both groups to a special contest. The winner is free to come and go at will, while the loser has to stay in Shangri-La until they learn to solve the problems.

Hacker's invention to clone himself accidentally clones Delete instead, leading him to produce 3 clones every time he sneezes. The kids and Digit enlist the help of clone catcher Cy Clone.

After crashing into each other's ships and crash-landing, the kids and Hacker must deal with bartering with one another to repair their ships. Also, Buzz and Delete suddenly become brilliant, and an evil genie named Warren disobeys his mother's orders to stay inside his bottle.

The kids chase Hacker around a building consisting of floors that have both positive and negative numbers.

A Sky Wall is built to protect Happily Ever After from Hacker, but he plans to invade when Wicked's operatic voice will break it. One of the Three Little Pigs secretly aides Hacker after a promise of protection from the Big Bad Wolf, so the kids have to do double duty to expose him and stop Wicked from singing.

Hacker has a statue which broadcasts his voice 24/7. This leads Cybersites to surrender once they can no longer bear it.

Digit and the Cybersquad are tricked into going to a land of giants, with Motherboard unaware of their presence. Hacker leaves them stranded, and threatens to send another deadlier virus to Motherboard. The Cybersquad must escape and stop Motherboard from receiving Hacker's virus.

Hacker pollutes Cyberspace with dangerous cyber-static by tampering with four satellites designed to keep everything free from cyber-static cling.