I need a plot device to link a series of seemingly "ordinary" unconnected murders to chaos cultists...

Once the murders come to be indentified as Chaotic, further factors become obvious; they form the shape of an eight-pointed star, etc etc

But before this, I need a hook to show that that in an Imperial city of millions, where there are bound to be plenty of "ordinary" murders everyday, some have come to official attention.

I was first thinking of simply having them all committed with the same weapon, but I can't think of a weapon (Or it's accompanying wound) which could be linked to the Ruinous powers (Without it being an obvious cult murder)...

Same blade, a piece broke off made of brass, each victim killed with 8 stab wounds in a particular way that left the victim alive bleeding out for 8 minutes.

Symbology is your friend.

But make some of the deeper things discoverable.

For now 8 wounds would at least peek a few people's interest.

Thanks, I appreciate the quick response but I feel most enforcers, especially a trained arbite would find that pretty easy to link
What I'm after is something that the group themselves discover that the local enforcement did not spot.

I'd say it should also depend on the type of cult. A Khornate murder will look different than a Nurgle one, for example.

For inspiration on the former, it might pay off to read a bit about the so-called Death Cults, most of whom are tolerated or even sanctioned, yet still skirt a very thin line towards Chaos worship (cannibalism, sanguiphilia, etc).

http://games-workshop.com/especialista/inquisitor/bestiario/assassins.html

With the latter, I would instead expect murder by infection with a deadly pathogen, its quality and elegance depending highly on the status and resources of the cult.

Generally, I'd say any murder that falls "outside the norm" in terms of intensity may be considered possible activity of Chaos worshipers by the authorities, though, simply because the depravity involved in such acts would brand the perpetrator a heretic who must have been corrupted. After all, why else would any human who is pure of heart and soul commit to such acts..?

As such, perhaps I would not let the authorities look incompetent by not having them connect such obvious dots. Rather, perhaps they realise that they lack the expertise with such things and bring in a specialist (the players) to draw on their experience concerning the paranormal, in addition to the enforcers' own knowledge on criminology and local underworld activities.

"We're not quite sure yet, but we think this might fall into your jurisdiction. Care to take a look at the crime scene?"

That is, unless you want to stage this on more of a backwater planet, perhaps a Feudal world whose leaders may have zero experience with grisly murders and cult activity. I'd say hives are just too much of a hotbed of cult activity to have local enforcers be completely in the dark.

Or perhaps each murder seems very simple, but each of the perpetrators are linked in some way...

They could all die of a sickness, but not the same sickness.

Or perhaps each murder seems very simple, but each of the perpetrators are linked in some way...

This sounds like a good start for a very dark scenario involving a couple twists.

The simple murders could mean that the Acolytes would not deal with experienced/hardcore cultists, but rather a much more insidious "ritual" that might link large parts of the population in some way; something where otherwise normal citizens with a job and a family would be compelled to go out and kill someone else. And you never know whether the friendly local you're dealing with is uninvolved or might just stab you in the back as soon as you turn away...

It could even be something like this:

First murder was a woman, killed by a hive ganger for spurning his advances.

Second murder was a child, killed by an errant servitor.

Third murder was an elderly man, killed by an angry merchant.

Fourth murder was an Arbites, shot by a vengeful prostitute.

While there is seemingly no connection at first, the more research is done, the more the players realize each murder has one link to another. Perhaps the woman's sister was the vengeful prostitute, who had been used & abused by the Arbites, who had arrested the Hive Ganger, who was the cousin of the child, who was the neighbor of the merchant, who was the father of the criminal that had been rendered into a servitor, etc.

Eventually it leads them to realize the only person unconnected was the old man. They then find each of the people had recently been to a specific shrine that is now abandoned, where they find a Tzeentchian cult waiting for them. Naturally, the cult knew they would come and they are prepared. They will undoubtedly be killed by the PCs. That is, of course, all part of plan...

the more research is done [...]

I think that's the primary issue with such elaborate schemes -- how would the players do this research if there was no apparent connection to begin with? In your average Inquisitorial game, the PCs aren't local enforcers; their Inquisitor would not send them down to solve four out of the 389.057.209.488 murders committed in that sector daily. Someone else (likely the local enforcers) must make the connection by themselves before the Inquisition would even have a reason to show up there.

Perhaps, then, there were oddly colored feathers in strange places around their murder scenes. The PCs are brought in to investigate the obvious Warp relation, only to be told they are found somewhere else, and then again, and again....

The enforcers would of course help with the investigation and save them if they are truly stuck, but I think it would be engaging for the players to find just how these seemingly unrelated murders are actually "birds of a feather"

What kind of cult are you wanting to run? That will definitely determine the orientation of the murders.

The enforcers would of course help with the investigation and save them if they are truly stuck, but I think it would be engaging for the players to find just how these seemingly unrelated murders are actually "birds of a feather"

Yep, that would work! Although, of course with the feathers I'd say we are once again at the "obviously connected" stage.

The enforcers would of course help with the investigation and save them if they are truly stuck, but I think it would be engaging for the players to find just how these seemingly unrelated murders are actually "birds of a feather"

Yep, that would work! Although, of course with the feathers I'd say we are once again at the "obviously connected" stage.

And thus the issue with investigations in Dark Heresy, I suppose. Either too easy to solve, or too hard.

And thus the issue with investigations in Dark Heresy, I suppose. Either too easy to solve, or too hard.

It'd be easier in a non-Inquisitorial game I suppose, where the players are local investigators assigned to what at first seems like an everyday case ...

Hmm, perhaps give just one or two murders an obvious connection to Chaos or heresy, so that the team has a reason to be dispatched? Be it because something strange was left at the crime scene, a witness saw something weird - or perhaps the victim was a relative of the Inquisitor's right hand, and as a favour to them, he/she wants to make sure that the culprit is brought to justice rather than being lost amid the red tape of a hopelessly overworked local law enforcement? Then when they investigate further, they could uncover the other links.

I particularly like cpteveros's idea. Here's mine if you want to throw it into the bucket:

Temporal Similarity - If the murders are perpetrated at the same time every day, or stranger all the digits of the time always add up to the same number.

Local Similarity - Likewise if one detail of the crime scene is always the same. It's always in a room with 8 walls. The bodies are always left in a certain pose (doubled over on the ground to pake the point of the star)

Geographic similarity - The distance between the first and second murder is exactly equal to the distance between the third and the fourth. This would also give an epicentre and a place to expect future murders, so I would be sure to make the distances large and point out to the players that the Imperium has no way of calculating anything exactly, so they only have vague areas.

I think PhilofCalth's way of tying them together is perfect. Those clues are innocuous enough to not immediately suggest an otherworldly influence, but odd enough to warrant a higher power's investigation. Maybe the PCs are on the planet for an entirely different reason, and someone they talked to/need to talk to is one of the ones murdered - thus drawing them in.

Thanks for the suggestions; I found a way to tie-in the murders, but now my players have actually surprised me and caught the culprit... Which I wasn't expecting. I could of course, have made an arbitrary decision that somehow allowed to escape, but I'm rolling with it and they've discovered that although he committed the acts, he was only the puppet of a powerful psyker using him remotely.

(Think Fahrenheit)

So now I have 2-3 sub plots to fold into the main investigation, including a rogue Inquisitor studying heretek xeno artifacts.

And thus, Dark Heresy shines.

How about have an Imperial sanctioned psyker had a dream about one of the murders. The murder itself could be ordinary but the psykers involvement would bring it to the attention of the authorities. For better results the psyker reported the dream to a superior was ignored and is now the first victim.

[oops didn't read the whole thread]