Fringe Season 1 Episode 18

When a second victim is discovered with injuries to the back of the neck, Fringe division is called in to investigate. Walter does an autopsy and discovers that the injury was inflicted by a human bite; the wound is infected by a rare genetically modified syphilis virus and all the spinal fluid has been drained. Tracing users of the virus leads the team to a scientist with connections to ZFT. His story leads the team to find more victims and a desperate race against time to track down a killer with a dangerous addiction to human spinal fluid.