Spoilers
“Young at Heart”

I’m starting to believe that I did not see very many season one episodes of The X-Files as episode 16, Young at Heart, is another one that I do not remember ever seeing before.
I also would hate to be a partner, friend, associate, co-worker, mentor of Mulder or Scully because they are always doomed. As soon as FBI agent Reggie Purdue walked on the screen and started talking to Mulder about the old days, I knew immediately that this guy was not long for the world… and damn, if I wasn’t right.

This was a tale about a killer that Mulder had caught early in his career, but not before the killer, John Barnett, had killed a couple of agents. Mulder had a clean shot, but did not take it because of the Bureau’s policy, and he blamed himself for the deaths after.
Barnett was supposed to be dead, having died in prison years ago, but it turned out that he survived and had been taken as a guinea pig for an anti-aging process meant to help cure the disease called progeria, a disease that causes rapid aging in children, by the prison doctor at the time, Dr. Joe Ridley. Ridley was doing human trials with his aging procedure, and they all failed, except for Barnett.

Barnett was also the X-Files version of Dr. Curt Connors of Marvel Comics (aka The Lizard) as he had grown back an amputated hand with use of some salamander DNA. That is never a good idea.
I liked this episode with the back and forth between Mulder and Barnett. It did not have a lot of X-Files-like weirdness, but it made up for that with a very creepy and vicious villain. It was also satisfying to see Mulder shoot and kill Bartlett at the end, making up for his previous non-action.