- Creepers (debut)
- Judge Trudy (non-speaking)
- Manny (non-speaking)
- Memoryville mayor (non-speaking)
- Merlin (non-speaking)
- Sheriff Judy (non-speaking)
- Stats (non-speaking)
- Bleak Pines
- Motherboard Control Central
- Grim Wreaker
- Spheres of Fears (debut)
- Northern Frontier
- Make-up trailer
In his latest and possibly maddest scheme ever, Hacker traps Digit and the kids in one of the dreaded Spheres of Fears, a mini-galaxy of orbs populated by eerie creatures called Creepers. He wants them out of the way so that Delete, in a diva star turn, can impersonate Motherboard and convince everyone in Cyberspace to cause chaos everywhere. No one can stop him now! To unlock the door and escape their Sphere, the kids must find the codebook—which Digit remembers is at the opposite end of the Sphere’s diameter. And there is no way any of them will make that creepy journey alone! As chaos builds in cyberspace, the team uses the relationship between circumference and diameter to overcome obstacles, and their fears, in the search for the codebook. But can they find it in time? If they fail, chaos will reign supreme, and Hacker will take over the virtual universe forever!
At the end of the episode, the CyberSquad finds the escape code
PI31415. The circumference-to-diameter ratio is named pi, after the Greek letter π that represents it in math notation. As the code suggests, pi equals about 3.1415.
Since pi is an irrational number, it cannot be fully written as an exact decimal. However, very precise approximations of pi have been calculated, yielding long lists of pi's digits, far more than are typically needed.
- Main article: Spheres of Fears/transcript