Are there any problems with spies amongst the players?

Question

As GM, I'm planning to, at some point, invite a friend from out of town who plays RPGs, to join our game with a appropriately levelled character.

This character (and the new player) is actually a spy for an NPC villain and would interact with the GM outside of the game to plan his motives and then he would be free to decide on whether he'll turn good or overthrow the villain, and the team are free to decide whether to let him join/go free/kill him.

With so much depending on the players, the spy and the party. Are there any particular problems with this approach? E.g. balance for 4v1 PC combat in particular systems (I'm running Pathfinder), meta-gaming headaches if the cat comes out of the bag earlier.

Answer 1

I've played in a few "he ain't one of us" scenarios. Some were fun, others were not. The one thing that made it fun was the GM's presentation of everything.

In one case, my character picked up some loot that (come to find out) was a major artifact and tied to a god of rot and destruction (my character played a ranger at the time, and was trying to become a warden of an area). Now, I realize that artifacts are ungodly powerful and all, but one day it went from a pair of gloves that gave a small bonus to spellcasting which I could take off at will to a pair of gauntlets that hurt my spellcasting, could not be pulled off, and no, you don't get a save vs. the magic. I felt screwed over and betrayed by the SYSTEM.

In another case, my character was screwed over and betrayed by another character because he was informed that a friend of his was a member of the bad guys. My character said "wow, Uma is a friend, I can't believe that". The other PC then spent a LONG time planning this assassination/disgracing for my character. However the Storyteller played it right down the middle, and I thought it was one of the better moments in our party.

Always play something like this down-the-middle. Do not favor either side. If your friend playing the spy screws up and gets strung up by the other party members, fudge no dice to help/hinder this from happening (I would even go so far as to get rid of the GM screen for these scenes). Also warn the spy that he may be killed very unceremoniously and you will not Deus-ex-maquina him out of trouble if that happens.

Answer 2

An important aspect to keep in mind is if this sort of thing is within the sphere of what the players expect to reasonably deal with. (In other words, the social contract)

If the players are expecting 'jolly adventurers roaming the countryside and slaying orcs', having a trap spring in the middle of the dungeon with the effect of 'your character is now mind-controlled, you should've prepared against mental invasion' is probably outside their expectations, and the players could be angry with you, even if you pointed to the module or rulebook and said 'It's totally valid'.

Alternately, if the players aren't thinking of intrigue and trustworthiness as an issue, if the spy succeeds (presumably harming the party or the party's goals), saying "You could've figured out that one of your party members had hidden motives" isn't likely to be seen as a fine explanation. This is doubly true because unless you and the player-spy actively drop hints as to their nature, because RPGs are created in terms of narration. If the players don't know to look for suspicious things, they won't.

To turn it back into a more concrete example:
GM:"You walk into the corridor. Once the door closes, spears fly out from the walls and floor. You are all impaled."
Players: "What spears?"
GM: "They came from the holes in the walls."
Players: "You didn't describe any holes."
GM: "You didn't ask."

In other words, nobody wins. On the other hand though, they could find the sudden change great. It's really dependent upon the party.

Answer 3

It is always a problem to hide things like this from your players. One of your players could take this personally, because it's you and the new player who are telling lies to him.

I understand that the opposite approach (having everyone know that the new player is a spy) might lead to metagaming and that your game system might be vulnerable to metagaming - the most common reason being that decisions taken by external knowledge can change the outcomes, like you suppose it would happen if "the cat came out of the bag early".

In a game that does encourage a particular behavior ("discover the spy and get rid of him" is way more advantageous in a D&D game than "the evil plot come into being", many other games give different advantageous outcomes for both situations.), I strongly suggest not to use this gimmick.

Answer 4

I've done this plenty. As long as players are mature it's not a big deal and can be very interesting. Using other people to run villains for one-shots or boss fights is great (no punches pulled, no "the DM was against us," just fair PvP) but embedded long-term betrayal takes more subtlety.

The main thing you have to do is balance the motivations. It's really easy for one PC to snuff one or more others in a usual freeform adventure environment - if his goal is "kill them for my evil masters" he's almost sure to succeed. Make sure he's only to observe and report or whatever.

I had a PC run an evil spy for a long time - in fact, the rest of the party never found out. He was a disruptive player and I suggested he play an embedded spy to sublimate his issues and it worked great - he'd be helpful and then rabidly scribble away his reports at night. He finally moved away and his PC retired to be advisor to a local count, but still narced them out every time they came to him for help.

If you intend the spy to be disposable and the new player's down with that, cool. If you want the player to become part of the larger arc, I suggest making him have some sympathetic motivation (e.g. "He has my sister!" or "He has geased me!") that lets the party "be OK" with taking him on after unmasking.