[This is an article about the wolf from Part 1. Click here for the article on the son of Julian Wilson and Maggie Warren.]
Mark (The Beta) was the second person infected by the virus, making him second-in-command to Jack. Later on in the story, he grows to pity the humans, even going so far as to assist them.
Not much is known about Mark before the outbreak. He was attending a rock concert the night the outbreak occurred, and it can be assumed that he lived somewhere in Oregon.
While washing his hands in the stadium's bathroom, Mark was tripped and infected by Jack. The two then began infecting random people, eventually claiming every person in the stadium. In the airport, Mark announced over the intercom that the plane on the last runway was still safe, though this was revealed to be a lie, and most of the people in the airport were infected as well. When Jack found Brian and dropped him off at the grocery store, Mark caught up to Jack and asked what all that was about, to which Jack replied: "That... that was my kid."
Later, Mark tested The Machine on two test subjects, which ended in disaster. When Jack asked if Mark thought him to be a good leader, Mark reassured him that he was- though he did this because was too cowardly to challenge The Alpha.
Mark decided to send out a search party to find a human to save the surviving test subject (who had severe internal injuries), which led to the finding of an unnamed man in a church. Mark assisted in the attempted surgery. With Mark's help, the man attempted to repair her internal injuries, but she started to bleed out of control, and died soon after. Jack decided to replace the dead test subject with the human man. When the man got word of this, he tried to flee but was caught by Jack, who went into a sort of feral state, during which he mistook Mark for a rival predator and scratched him across the cheek. Once Jack returned to his normal state, Mark argued from the man's life, but was threatened into submission. Mark was then forced to take the man to The Machine.
When the man was transformed by The Machine, Mark pitied him and tried to help, but the man found his way to the roof and hanged himself with some IV tubes from the infirmary. Jack remarked that "humans are of no help", which gave Mark an idea.
When Brian's group was captured and escorted to the hotel, Mark took Ali into the bathroom to propose a deal. Ali then conveyed the proposition to the others: the survivors help Mark murder Jack, and Mark will spare them. Shahbaz then informed Mark that the firebombing would certainly kill everything inside the blast radius, including the no-longer-invincible wolves, much to Mark's shock and disappointment. He then asked to instead be taken along in the helicopter evacuation, to which the group agreed.
However, when Jack was called into the room alone, Mark found that the silver knife he planted earlier was missing, causing him to abort the murder. Once Jack left, Jeff handed Kelly a hand grenade and escaped through the window. Jack told Mark that he knew about the murder attempt, and warned Mark not to challenge him again.
Later in the day, Mark took Rico and Wolfgang aside, and told them to leave Chicago due to the firebombing. Wolfgang recognized that Mark had betrayed Jack. He informed Rico of this, and Rico started to leave to tell Jack of Mark's betrayal. However, Mark lashed out and slashed Rico's throat. Mark then threatened Wolfgang. After Mark left, Wolfgang left Chicago in fear.
That night, Mark reluctantly activated The Machine on Brian and Kelly, though was sure to not infect Brian. When Kelly destroyed The Machine, Mark and Jack fought while the survivors made their way to the roof, where Jeff was scheduled to pick them up. In the fight, Mark tried to kill Jack, though his enemy gained the upper hand, savagely eviscerated him, and hurled him to his death.
While the two of them were fighting, Jack managed to blind Mark, eviscerate him, and throw him out a window.
- The name "Mark" is what The Beta decides to name himself. It is unknown whether or not this is his real name.
- Mark is the first wolf to directly challenge his Alpha.
- It is possible that Mark was some sort of medical professional before he was infected, given that he had some knowledge of what to do during the surgery.