Case 02, File 18: Fearful Symmetry

AKA: I Refuse To Make A Hamarabe Joke

The X-Files is rarely, if ever, maudlin. It gets sad sometimes, but the list of TV shows that don't is almost entirely restricted to sitcoms (and even those get sad sometimes). Being overly sad or mopey is sort of against the tone of the entire series, since it needs to stay light and exciting. But, there are subjects that are inherently so sad that it's hard for the series to overcome them to stay light, and one of the big ones is animals dying.

Case 02, File 17: End Game

AKA: We've Got Like 7 Seasons Left, Calm Down Title Namer

There would come a moment in every single Samantha fake out where the series had to bow its head and fess up to the fact that it had been full of shit. How it handles that moment would often go on to define any given fake out in the minds of the audience, since it tends to be how they remember the event. Well that, and how they hint that Samantha might still be out there.

Case 02, File 16: Colony

AKA: Attack Of The Clones

Samantha's abduction is pretty much one of the most important parts of Mulder's character, to the point it could be considered central to the audience's understanding of him. Which is why it's so odd that when the series teased him with Samantha's return (as it would do several times over the course of its 10 season run) it never seemed to know what to do with it. The teases never seem to have much long term affect on Mulder, and the series certainly doesn't devote a ton of time to each individual tease, which makes them all feel like a bit of a letdown.