Dr. Nancy Jaax and her lab partner, Dr. Peter Jahrling, must take matters into their own hands to determine the source of the virus before it spreads; Dr. Jaax convinces an employee to hand over samples from infected monkeys.

When representatives from varying agencies disagree on how to handle Dr. Nancy Jaax's discovery, she realizes there are few protocols in place for containing a deadly virus on U.S. soil; an employee at the monkey research facility falls ill.