Shortly after diagnosing cancer in a patient just by looking at him, a Pittsburgh EMT named Leonard Betts is decapitated when his ambulance is hit by a truck. He still manages to leave the morgue without his noggin. Scully suspects body snatching for medical purposes, while Mulder is open to the idea of a headless Betts walking around. The agents find Betts' head in a bin of medical waste, and it still shows signs of life when Scully examines it. At Betts' apartment, Mulder finds a bathtub full of iodine and a fully-headed Betts rises from the tub shortly after Mulder leaves.
Meanwhile, security camera and PET scan images of Betts are showing a strange fogging up. Betts' head undergoes a biopolymerization process and is cut into slices, and a pathologist finds that the entire head is riddled with cancer. Betts' partner thinks she hears him over the dispatch. Mulder proposes that life force (chi) may be leading to the fogging effects; a photographic examination suggests a ghostly image of a body joining the head slice. Mulder thinks Betts may have been cancerous by birth and was able to regrow a new head like lizards are able to regrow tails.
The agents find that Betts had an alter ego named Albert Tanner, also living in Pittsburgh. In talking with his mother, they find a photo of a man identical to Betts in her home, but the mother says Tanner died in a car wreck six years ago. Betts' partner finds him, and he apologetically kills her with some sort of injection, apparently to hide his secret. He is caught and handcuffed to a car by a security guard, but escapes after detaching a thumb. The agents find his car full of cancerous medical waste, and Mulder wonders if it's "snack food" for a Betts who has evolved beyond human limits and needs to eat cancerous growth to survive.
The car is registered to Mrs. Tanner, who denies that her son would kill anyone. But Betts ends up killing a man suffering from lung cancer soon after, using his heightened abilities to detect the illness. In a storage locker, Betts sheds his skin to grow a new body. He tries to escape in a car as Mulder and Scully arrive, but they shoot and blow up the vehicle. Mulder thinks this second death is a ruse. Sure enough, Mrs. Tanner is helping Betts back to life with an iodine bath. He thanks her by removing her lung for a nibble.
Betts, who has caught a ride atop Mrs. Tanner's ambulance, tries to attack Scully, leading her to realize that she has cancer. She manages to kill him, apparently for the last time. Scully wakes up hacking with a nosebleed.
Paul McCrane, who plays Leonard Betts, also played Dr. Robert Romano on ER
Episode Body Count
Michele Wilkes: killed by Betts after he injects her with a lethal dose of potassium chloride.
John Gilnitz: dies of blood loss after his left lung is removed by Betts.
Leonard Betts: pronounced dead after Scully blasts him in the head with a defibrillator. Kind of difficult to keep track of the number of bodies he produces, but apparently they're all one person in the end.
Cumulative Body Count (85/202 episodes, 0/2 movies)
Grand Total: 1,145
5 weeks ago