John Carpenter's The Thing: The Party Game

Premise
A hostile alien entity has been discovered in a remote archeological outpost. This entity can take the shape of anyone. Who do you trust? Are your senses deceiving you?

Setup
This is a party game meant for a room full of a lot of people, somewhere around 10-25 people is ideal. More than that, and things get kind of chaotic. Fewer than that, and the game is too short.

Choose a person to be the Game Master. By drawing cards out of a hat, choose some people to be Soldiers. Choose others to be Archeologists. The Soldiers and Archeologists should be in equal number. Everyone else is a Local. One person among all of these players is secretly The Thing.

The soldiers, archeologists and locals have some special features that distinguish themselves from one another.

Locals: Get one vote and one Trust token.
Soldiers: Get two votes and no Trust tokens.
Archeologists: Get no votes and two Trust tokens.

Play
Step 1: The Thing
The GM tells everyone to close their eyes. The GM tells the Thing to wake up. The Thing walks around the room and chooses a victim by tapping him or her on the shoulder. The Thing is now out of the game. The victim keeps his eyes closed, but becomes the Thing in the next round.

Step 2: Voting
GM tells everyone to open their eyes. Everyone votes for who they think is the Thing. The person with the most votes is out of the game unless someone spends Trust tokens.

Step 3: Trust
Other people can spend Trust tokens on your behalf to cancel out votes. One token cancels one vote. Once Trust tokens are spent, they cannot be used again for the rest of the game. If as a result of token-spending there are zero votes, continue from Step 1.

Victory
If there are two people left in the game, the Thing wins. If the Thing is voted out of the game, everyone else wins.