When a grave with three unidentified bodies is found in a forest preserve, the BAU is called in to investigate. The victims are covered in bite marks and show evidence of being held captive before they were killed. The M.E. report reveals two of the victims suffered from both animal and human bite marks. Reid suspects the UnSub infected them with the Rabies virus via the first victim, an animal control employee who was the only one not bitten by a human. Their profile of the UnSub notes his obsession with Rabies and watching his victims suffer from the virus.As two more locals are reported missing, Garcia uncovers a report from fifteen years ago of a nine year old boy, Hunter, who was bitten by a bat on a family camping trip. They hone in on his older brother David, a pest control employee, and raid his house to find tape recordings of Hunter suffering in the hospital. The absence of Hunter's death certificate leads them to believe his parents euthanized him to put him out his misery. After the team is alerted to a crazed woman attacking patrons of a coffee shop, they head there to apprehend her and locate an abandoned animal shelter nearby which turns out to be David's infection lab. The team takes him down and is able to save one of his would be victims.