Child of Hypnos said:
they're a mercenary lot - admittedly only one has the Charachter background of being a merc, but theyre all in it for either money or Power. - i figured i have someone they know murdered and if that doesnt work ive got another method - the classic 'it might be me next' hook.
I'm trying to come up with something now... watch this space.
edit: Here we go. I don't know how well all this would work, it will probably take some more thought, but it is what it is.
NPC Group is doing something bad to some people, including Bob.
Bob wants to fix the problem. However, Bob can't fix it unless he calls on the demons. Which he does. The demon is summoned into Bob's daughter. Little girls who are evil is a popular theme, so there you go: demon in little girl. Demon type = whatever CR makes a good final encounter.
The demon goes ahead and kills someone from NPC Group. That's our murder.
The demon is now released and wants to gather souls/do evil stuff. So she keeps up the evil stuff. Maybe inciting violence against NPC group.
Bob benefits from all of this, and maybe he doesn't like what's going on but he writes it off as worth it to fix the problem.
Bob sees how he could solve more problems if he does more of this kind of thing, so he gets a little cabal going to summon demons FOR GREAT JUSTICE! (ie. they think they are doing good.)
Eventually, more people are possessed by demons/more demons are called in and things just start going crazy in town.
Enter the PCs.
They are given a job to track down the murderer. They are given a lead. The guards are in on the whole Bob cabal so they aren't doing much.
PCs come across some kind of riot. Let's say a demonstration gone wrong. Obviously, it's that person using magic to cause all this trouble. That person is running away. But look over here - the mob is about to string up someone else and burn him alive. You can't save the guy and catch the person who fled. (They might have been paid to rescue this guy as a side quest.) What do they do?
Bob confronts the PCs. (This would work much better if Bob is related to one of the PCs.) Bob tells them what he did, and he explains/justifies his reasons for it. He's planning to cause more problems, and warns the PCs that if anything happens to him, bad stuff will happen to them (he'll sic the demon on them). What do they do?
Bob and/or his cabal approach the PCs. They want the PCs to work for them and will pay more. And they don't want the PCs to say no (violence is the other option). If they do say yes, the NPC Group will react as well. And let's say in order to prove their new loyalties, they have to off this guy the cabal captured (innocent guy). What do they do?
One of the demons approaches the PCs. He'll agree to give up the whole thing if the PC will submit to being possessed. The demon's ready to sign a pact that he won't make the PC take any specific action - he'll just tempt. A Paladin or Cleric or any Good PC would be a good choice here. Or a neutral PC who is on the slippery slope to Evil. Anyway, if they don't agree to it, the demon will kill the host body and sneak away, ethereal.
Bob tells them who and where the real killer is. They go confront the demon - who is a murderer - who hides behind the little girl - who is innocent. What do they do?
A demon comes forward and is willing to be taken in by the PCs as the murderer. It's no big deal to the demon; it can just leave the body to rot in jail/be executed while it goes to possess someone else. (The PCs should know this.) The PCs will be paid their reward. (This one isn't so good, since it can resolve the whole thing easily. Or maybe it goes into someone else and that person kills another guy from the NPC Group and the NPC Group is pissed off at the PCs - "We paid you to get the murderer, but you didn't!" Maybe expand the scope of the PC's job.) What do they do?
The PCs are alerted to the location of the demons' bodies. Which are guarded by fanatic innocents (charmed or whatever). They'll have to do some violence in order to get to the demons. How many people are they willing to smash in order to get to the demons?
I was assuming the possession rules from the Book of Vile Darkness.
Anyway, there are the examples of a murder "mystery" solved early on. It's not about whodunit, it's about how the PCs react to all these things (what's going on/the backstory).