A subaquatic earthquake causes the breakdown of one of the supporting pillars in the McDuck oil rig. Donald finds out about this when he watches the Channel 00 news. Lyla Lay interviews Scrooge McDuck, who is satisfied that the technicians made it off safely and the oil spill was prevented, yet regretful as the insurance company that will cover the damages is his own. Uno tells to Donald that not one seismograph registered any tremors at the time of the earthquake, save for those of Ducklair Tower, which at the very same moment registered other four symultaneous earthquakes, as if the seismic energies of these earthquakes are being guided and controlled on a level that can avoid being detected. All six earthquakes took place exactly 50 nautical miles from the edge of the Cromwell's Fault, the edge of the continental plate that Duckburg rests on. However, shortly before the earthquakes, Uno registered slight electromagnetic anomalies, meaning he can predict the next earthquakes, but these anomalies won't tell much until analyzed in depth, so Donald dresses as The Duck Avenger to check the place of the incident, the McDuck oil rig. For this, Uno gives the Avenger a Techno-Diver vehicle and scuba gear
Near the rig, a PBI ship detects the Techno-Diver approaching, so Mary Ann Flagstarr sends a squadron down there. The Avenger finds men from the Environmental Department at work below the platform, but then he is intercepted by PBI agents who want to bring him to Flagstarr, but he manages to escape.
Back at Ducklair Tower, the Duck Avenger is worried to become a wanted fugitive for interfering in a government operation, but Uno reassures him that it won't happen as the PBI will likely keep the case a secret. Now, if the PBI and the Environmental Department are both investigating the earthqueke, there must be something interesting there.
At the Environmental Department, agent Flagstarr reports to Professor Morgan Fairfax, the chairman of the department, that the mission by the oil rig was discontinued due to intrusion of the Duck Avenger.
Uno tells the Duck Avenger to use the TII (from the second issue) to check info at the Environmental Department's terminal. The Avenger refuses at first, as he has done enough illegal intrusions for today, but Uno convinces him that they are not going to steal nor hack data, just investigate. They use Angus Fangus' computer as a bypass to not be detected. They find that Fairfax has been studying the underwater foundations of the oil rig for years, and he's running a research program that deals with exploiting the underwater territories. The Avenger and Uno are detected by anti-virus programs and must flee, and the PBI traces and interrogates Angus, until they find that his computer was used as a bypass and the original source cannot be traced.
The Duck Avenger goes to the Environmental Department labs. He manages to bypass the voice and retinal scans since Uno registered them when Agent Flagstarr was interrogating Angus. Then the Avenger uses special lenses to see the security lasers and tries to continue through the air vents, but the X-transformer shield gets stuck there. When trying to adjust the shield, he accidentally activates a propeller and falls just in front of a guard. The Duck Avenger defeats the guard and gets his access pass to Fairfax's lab. There, he connects the X-Transformer to Fairfax's computer to know everything worth knowing in the department's archives. At that moment, Fairfax arrives and, believing the Avenger may know something about "project Pangea", shoots a can of phosphor to kill the Avenger making it look like a disaster caused by the hero, and leaves taking a briefcase with him. Luckily, the Duck Avenger manages to use the X-Transformer to fly away, and also saves the guard he defeated earlier. Fairfax pretends to be injured by the fire and gives Mary Ann what he claims to be his late wife's one-of-a-kind lucky charm, then he gives his final wish to take a plane that is waiting them.
After processing Fairfax's archives, Uno discovers project Pangea, a project not even Fairfax's closest collaborators know about, to induce the most devastating earthquake of all time. the professor created six magnetic intensifiers and placed them in the places where they would eventually cause the earthquakes. The first time was to test if they would be detected, but the next time it may cause the entire west coast to sink into the ocean. Fairfax's plan is that the detachment of the coast will induce a major change in the undersoil which will cause an enormous earth plate to be raised to the surface, giving people vast uncontaminated territories, new sources of food and more space to inhabit. The Duck Avenger wants to stop Fairfax, but Uno insists that while killing millions, it would save billions and therefore refuses to help.
The Duck Avenger takes a jet to reach Fairfax, then jumps on board of his plane, causing a bump that knocks Mary Ann out. Fairfax fights the Avenger with an axe and hits the X-Transformer away. Flagstarr wakes up and stabilizes the plane, and the Avenger saves Fairfax from being thrown away by the decompression. The Avenger asks Fairfax to stop the earthquake sequence, but two keys have to be used on the briefcase to do it. Mary Ann approaches, gun in hand, and the Avenger tries to convince her that Fairfax has been lying to her, which she realizes when she finds Fairfax has another of the necklace he claimed was one-of-a-kind. The Duck Avenger deduces the necklaces are the keys, but they still need a deactivation code. Luckily, Uno has changed his mind and connects to the briefcase, quickly finding and loading the code and then apologizes to the Duck Avenger as there's a big difference between what's logical and what's right.