(Covers information from Anderson's universe)
As Raccoon City entered the night and the T-virus infection spread, Mackenzie and Marla were forced to run upstairs to the roof of their office block. When Marla tripped, Mackenzie refused to go back for her due to the approaching the Undead. Closing the door to the rooftop after himself, it forced her to type in a number code to escape, resulting in her being bitten.
While Marla died, Mackenzie made it to the ground floor by his own way and hid in Raven's Gate Church. Armed with a gun, he tried to force out the newly arrived S.T.A.R.S. officers Peyton Wells and Jill Valentine, and TV weather girl Terri Morales. The noise got the attention of a pack of Lickers also hiding in the building; separating the group, they chose Mackenzie as their victim.
- Much of Mackenzie's scenes were cut out of the cinematic and home releases.
- Mackenzie is a Scottish name. In a deleted scene, Peyton asks about the "Irish guy" to which Terri corrects him. Jill says that he was Scottish, and Terri deadpans "Oh".
- Mackenzie is referred to as such in a longer version of the office block scene.