Tyler

Tyler was a scientist employed at the National Health Services building in Los Angeles during Day 3.

Day 3

Terrorists dropped off the almost unidentifiable corpse of a drug dealer at the NHS vehicle ramp, and exploded a bomb to draw attention to it from a security guard. Tyler and Dr. Sunny Macer responded in HazMat suits when it was determined that the corpse had been infected with the Cordilla virus. Tyler recognized some of the characteristics of this kind of virus, and was sent by Dr. Macer to perform a series of tests.

Tyler appeared later with Chase Edmunds and team in gas masks at the residence of Susan and Bill Cole, where they were tracking the possible spread of the virus. He reported to Chase a bloody tissue, which guaranteed that Bill was symptomatic with the virus.