When several people in Los Angeles suffer from seizures as a result of product tampering of over-the-counter medications, Don and his team discover that a former chemist from a large pharmaceutical company is to blame. While tracing the culprit to the Sibley mountains, the team meets up with Special Agent Edgerton (Lou Diamond Phillips), who is tracking a cattle rancher-turned-federal fugitive for selling tainted beef and killing a U.S. Marshall. Megan figures out that their meeting isn't random, as the two fugitives have something in common.