Anyway, we watch as a CDC team opens the trunk of a car and removes a briefcase, and then Walter's arriving at the scene again, telling Broyles about his hypothesis as to how the virus behaves: "This virus has to spread itself, but in order to do so, it needs other organisms to infect," Walter "explains," even though what he's saying amounts to "It has to spread, but in order to do so, it needs to spread." Walter says it wasn't until VandenKemp was in an office full of people that he sprayed. "But having successfully infected other people, I believe that the virus now senses that it's contained within the building, and ... and it wants to get outside to continue spreading." Broyles is all, "The virus wants to get outside? Doesn't that strike even you as a bit far-fetched?" Walter points out the courier only spewed as he approached the outside doors, and then the receptionist hurled herself outside before she sprayed. "The virus compelled her to leave the building. It wanted to get outside." "You're saying the virus made her jump," says Broyles, and Walter's all, bingo! They could call the virus Kris Kross!

Then they go into a tent, where we watch some video feed of CDC techs poking around at a cylinder of material they found in VandenKemp's briefcase. "Among other things in the briefcase, we found a drill core sample from an exploratory dig." Microscopic shots of black stuff and red stuff! "This is our virus," he says.

After the commercial break, we learn that the sample was stolen from Solum Oil Corp., and should have been stored in an airtight, protective case, and it came from 10 miles below the surface. "In that case, I believe we're in the presence of a 75,000-year-old terror," says Walter. Always keeping things clinical, our Walter. He suspects this virus might have been responsible for wiping out the ice-age mammals. "Some things are meant to be left alone," he adds.