On October 27, a fax was received at AFAO.com, listing a number of US cities. Over the following days it was updated with specific coordinates and instructions for retrieving packages at those locations. AFAO also linked to Metastasis, where a 'game' of sorts allowed people to experiment on viral samples. Those who retrieved packages also found subject numbers which unlocked additional test cases for experimentation. Once any test case was solved, a new document would be unlocked.
The unlocked documents contain frames which form a graphic story. Some also contain clickable regions which play audio or video, or reveal other resources.
The story begins in American Protection Camp #83, situated outside of Billings, Montana. It was out of reach of the Liberty Defense Perimeter and was struck by spire missiles, infecting the townspeople with Crawlers.
Thirty miles to the west from the protection camp, a group of American soldiers fights off a group of Hybrids. Sniper Jimmy Sanchez is told by an officer to be needed in an installation in near Keystone, South Dakota. Sanchez points out that Keystone is within Chimeran territory, which the officer replies "not all of it." In the war ravaged city of St. Paul, Minnesota, demolitionist Corporal Lee Dashiel is also called in to Keystone's installation.
Dashiel arrives at the installation beneath Keystone where he meets Sanchez and Sentinel Nathan Hale, who summoned them. Hale explains to the two men that their expertise are needed on his near suicide mission in a conversion center near Salinas to find Dr. Silbermann who has a special new inhibitor before the Chimera find it.
The next day, Hale, Sanchez, and Dashiel infiltrate Salinas. Sanchez shares his mistrust towards Hale for being a "stink" with Dashiel and the fact that whenever someone accompanies with Sentinels, only the Sentinels survive; Dashiel, however, trust Hale. Suddenly, the three are attack by Chimeras. After defeating them, the three hurry on. The three then enters to a makeshift conversion center, where they discover the buildings is entirely fill with cocoons. Hale examines the cocoons and finds Dr. Silbermann in one of them. A very weakened Silbermann states that he has the inhibitor, and wants himself to be killed before he turns. Despite insistence from Dashiel in saving Silbermann with the inhibitor, the doctor states to not waste it on him as it is the only one of its kind to be duplicate. Suddenly Spinners discover them and a firefight ensues. After the Spinners are all killed, Dashiel is mortally wounded and Sanchez is infected. Sanchez forgives Hale for everything he criticized him, and begs to be killed before "turn[ing] into a monster" which Hale grimly complies. A dying Dashiel also bids Hale goodbye before succumbing to his wounds.
Hale destroyed the facility and has Dr. Silbermann's inhibitor.