The episode starts with a nice side view of Mainframe floating above a turquoise and purple sea, with a water vortex lined up under the very center. The camera starts outside of the Kits Sector; the tall buildings of Baudway are to the right and Hex's Los Angles is floating off to the left. The point of view zooms in and pans left. As the camera rises, the tall thin towers of the Kits Sector are to the right, and Floating Point Park to the left looks like giant pieces of a jigsaw puzzle, covered with grass and stacked at different levels. The point of view descends slightly when it is directly over the lightly tinted tiled terraces of Beverly Hills. It approaches closer as the oval shaped towers of Wall Street come into view, and then the dark industrial sector of G-Prime. By the time the camera circles over Baudway, the view is dominated by a close up of the Sub Sphere.
Suddenly a portal opens up, and from it appears a really mean looking creature, one totally unlike anything else seen before.
Meanwhile, back at Bob's apartment, the Guardian is working on his old car as Dot tries to provide assistance. "Sounds to me like it's a fried initiator." "No, just a distended turbo lock." Bob is bound and determined to mend this car, and commands Glitch to become a multitool, but he pauses as he senses the sinister creature moving about Mainframe.
Phong is having problems with his Vidwindow in the Read Only Room, when the creature pulls its thin bony body out of a portal right on top of Phong. It seeks the Codemaster, "Talon". Phong tries to run away, but the beast pulls off some fancy martial arts moves, and has Phong in a force field.
Enzo and Frisket are in an out of the way corner of Old Man Pierson's Data Dump. They enter an old shed, clearly marked with the international "Do Not Enter" sign, in search of parts for Enzo's air cart. There's a lot of neat stuff, including something that looks like a cross between a muffler and a bagpipe with six horns. The big find is clear lavender rod with a knob on one end. Old Man Pierson barges in, but the creature calling for Talon interrupts his lecturing. The sound of its voice leaves Pierson quaking in fear.
Bob and Dot jump on their zip-boards and the precise path from Dot's Diner to the Principal Office is shown. When Bob declares, "you're a Codemaster. From the Web?", everyone gasps. "No," replies the creature, "you are fortunate, I am from the Net". Bob tries to convince the Codemaster that there is no one named Talon in Mainframe, but gets knocked several thousand feet into the air. When he comes down, Glitch has been immobilized. The creature vows to take Mainframe apart, sector-by-sector.
Dot starts evacuating Mainframe. All the vehicles are in use, but she needs more. She tries to rent some from Megabyte, but he refuses to get involved. "Codemasters and Viruses have a rather unpleasant history." Phong tries to remove the lock from Bob's arm.
In the Read Only Room, Phong shows Bob a hologram of a Codemaster. They are mercenaries, intersystem eliminators. They are the most vicious society to inhabit the Net, even the Web. Their Gibson-coil Pike is deadly. Long before Bob came to Mainframe, Talon sought refuge, changed his identity, and now lives among the people of Mainframe.
Enzo overhears the conversation, and concludes that Old Man Pierson is Talon. He flies to the Data Dump. The old man had taken a vow to never again delete a living being. Unable to convince Pierson to fight, Enzo accuses him of being a coward.
Bob tries to scoop up the Codemaster with a data retrieval crane, but is foiled. The Codemaster is distracted by an incoming game, and Bob convinces it that the game cube has more power than even a Codemaster. His plan is to help the User win, which will nullify the stranger and Bob too.
It's a Wild West game. The train station is in the town of Spuzzam. Bob helps the User, who disconnects the engine from the rest of the train. He explains to the stranger the consequences of losing the game; total nullification, but will allow his friends to live. It is the Guardian tradition. This impresses the Codemaster.
But then he hears Enzo's cry for help. The boy was the Engineer on the locomotive, but is now tied up. As the train bends around a switchback, Bob lassoes its smokestack from across the gorge and pulls himself in with a "Yee Haw!”. He yanks on the User's tie, causing "Game Over".
Back at Dot's Diner, Bob is giving Enzo a good talking to, when they are interrupted by the Codemaster appearing at one end of the street. At the other end of the street, a second portal opens up, and out steps Old Man Pierson. The stranger declares "I, Lens the Reaper, hereby do challenge you, brother Talon, to a game of High Spy". Pierson denies the challenge, "tell the guild masters that I'm out of circulation". "No one leaves, the Guild; it is tradition" says Lens as he glares meaningfully at Bob. The stranger grows to enormous size, but instead of aiming his pike a Pierson, unleashes it into the sky. The sky becomes roiling blue and red as a result of the paradigm shift.
Bob steps in front of Pierson, blocking the Codemaster. As do Dot and Enzo. In all his days on the Net, the Codemaster has never seen such a "despicable" display of honor. He leaves Mainframe, to tell the Guild that Talon is no more.