D is for Doppelganger

So Doppelgangers, right?  At first glance, I was tempted to dismiss them.  A gray, featureless humanoid who can polymorph to look like anyone?  That's just like "The Thing" or "Invasion of the Body Snatchers," except with less flair.

And then I realized: Wait- Doppelgangers are just like "The Thing" or "Invasion of the Body Snatchers!"

"The Thing" was cool because there was this disgusting Thing that either looked like something completely recognizable (a dog, a human, a wolf, etc) or some hideous, foetal amalgamation of all sorts of creatures.  But ultimately the real horror of the story is that anyone could be The Thing- it was psychological horror at its best.

"The Invasion of the Body Snatchers" was cool because there were these emotionless alien "pod people" who would subsume you while you slept and create a duplicate, nearly indistinguishable from the original except for the utter lack of emotion.  The terror there was more of a zombie terror- something familiar turned into something slightly unfamiliar- but it was accomplished through the same means.

The trouble with Doppelgangers is that, to a certain extent, they're a known entity- "The Necromancer you just slew begins to melt and shift; after a few minutes, all that's left is a featureless grey body."  "Ooh, a doppelganger!"  That's not very exciting.  Also, what made the psychological horror movies above thrilling is that anyone could be the enemy!  In a game of Dungeons and Dragons, you know who your friends are- the people at the table- and you know who the enemies are- the DM, and almost anyone played by him.

Once these problems are identified, however, they become pretty easy to solve.

I think the key to solving the first issue is to introduce the fact that there are Doppelgangers at work very slowly.  The NPC the players should first unmask as a Doppelganger should be someone they've worked with for quite some time, and the players should be left to wonder how long they worked with an ally, and how long with an enemy.  Quickly, it should become clear that there's a conscious effort, on the part of a large (perhaps infinite?) group of Doppelgangers, to take over a region.  The threat is not just a single doppelganger working mischief- the threat should be an army of Doppelgangers, and you can't ever really know who's who.

Next comes the really mischevious part- ensure that one or two characters spends some time off on their own.  Take every player aside and roleplay a small interaction separate from the group.  And make it clear to one of the players that their character has been captured, and that when they return to the group, they are a Doppelganger, infiltrating the group but whose motives run directly counter to the real players.



Doppelgangers.  Featureless, pallid grey humanoids with four fingers to a hand, their central finger contoured like two fused together.  Everything about them is an amorphous, foetal suggestion of real features.  Given five minutes alone, they can morph their body to look like anyone they've spent five minutes with.  Where do they come from?  Who knows?  Some say they're fungal plant-creatures from deep within the bowels of the earth, slowly nursing an ancient hatred of surface dwellers.  Some say they're formless aliens descended from some region unknown.  Some even whisper that Doppelgangers are just a natural psycho-magical mutation of some normal humanoid; exposed to cosmic or arcane forces, and changed to a shadow of their former self, forever unable to recapture their original appearance.  What are their motives?  Do they disguise themselves among us for study?  For entertainment?  Or do they enjoy the sport of the deception, establishing trust with a target before moving in for the kill, allowing one of their own to move in place for further deception?