Okay, here's the story for this weekend:

The Empire (well, Sith Empire - but the end result is the same) want to cause some clandestine trouble on the player's adopted world. They hire some low rent thugs from the Bad Side of Town to mug/rough up/murder an NPC, invoking a (probably) violent response from the players.

Now, finding the gang that did the attack - that will probably be pretty easy. However the Agent will have been smart and not advertised his elegance. The extent of his transaction will be "Here's a large sum of money. Go beat up Person X".

So I'm having trouble connecting the dots from Thug to Agent. The most the thugs will be able to say is "Yeah, we were paid by a well dressed fellow to do this" and be completely truthful. So, any ideas how to bridge that gap?

How were the thugs contacted originally? Trace that back. Where did they meet? Some kind of connection. How were they paid? Kind of payment possibly to be traced.

The transaction could have been caught by a random security cam at the transaction site.

Players would then have to trace the owner ship of the footage (e.g. seedy shop owner or large corp warehouse), negotiate to gain access to it (or steal it, or do an odd job or some other type of side mission), and then try to pick out any noticeable details of the "agent" from the very poor video quality.

Once they have some kind of key feature of the "agent" (e,g, gang tattoo, cybernetic eye/arm/leg, or fancy side arm, etc), they can then begin to ask around and track down leads to see who the "agent" could work for.

"Yeah, we were paid by a well dressed fellow to do this"

Seriously though, Arrakus beat me to the security cam.

What about...

The Agent called back and happy with the last results wants to hire them again.

The Agent did the half up front/half upon completion thing.

The agent paid in plastibills and those little metal bar things instead of conventional cred stick e-trade, so there's DNA and prints to run through a database.

One of the thugs took a selfie of himself with the money and Mr Johnson is in the background closing the deal.

The gang was contacted by the Imperial at a local watering hole. The watering hole is also patronized by a very observant local. The Imperial agent may have tried to look the part, but the local might have picked up on something he would be familiar with that somebody else might not have known ("They said they were from Town X, but I'm from Town X, and he [did thing], and nobody from there would..."), or the local noticed them coming from the local transportation hub/starport, giving the PCs a place to look for.

Personal details: Did the agent have an accent? (Specifically, an Imperial accent?) What were their mannerisms? Quality of their clothing? Were their boots clean? Were their hands calloused? Did it sound like he/she was educated?

Once they've narrowed that down, they should look for transporation logs: How did the agent arrive on the planet? What was their point of origin/embarkation? How did they pay, and did they return to the same place?

One of the thugs took a selfie of himself with the money and Mr Johnson is in the background closing the deal.

Oooh, I like that. The Agent has his S locked up tight, with a flawless hiring, his tracks are covered, everything is perfect - and the whole thing is blown because someone randomly snapped a selfie that he didn't know about. That's sublimely ridiculous.

The security camera thing works too - and they're in good with the business folks, so this is a logical avenue to pursue.

Grilling the thug for personal details might also work, and would certainly throw enough suspicion towards the right directions.

Cool - okay, this gets me past my writers block. Thanks guys!

Variant of the selfie angle - one of the thugs has a cybernetic eye that features a camera, and he habitually records or takes photos of things. They are then stored inside some neural cybernetic or his datapad or whatever.

(That way, even if the PCs kill everybody, they can still retrieve the data.)