Soft Light
In Season 2, Episode 23 of The X-Files, Agent Scully and her former student act as a doubled pair. Both are styled very similarly, and it is obvious from the beginning that this young character was created as a foil to the older FBI agent. Both are very similar in personality, and both share nearly identical skepticism to the fantastic circumstances in which they find themselves. The differences are minor, and these differences cause the younger character’s subversion and demise.
Doubling
The doubling between Scully and her former student is meant to mirror the doubling of the Scientist and his shadow. From the beginning of the episode, I was absolutely sure that because of the similarities between the two women, one would not survive the episode. I had seen later episodes, so I knew that Scully would survive and that it would be the younger that would die.