My party is about to go to one of the hideouts of the organization that they have been trying to stop, but the nations CIA/MI6 type group has already shut it down in the last couple of weeks. The party is aware of this, but they are going to see if they can find anything else that may have been missed. I don't want them to necessarily waste their time, so I want something to be able to be found, but I'm not quite sure what. Does anyone have any ideas for what they might be able to find?

Quote from Koaltrain >>

My party is about to go to one of the hideouts of the organization that they have been trying to stop, but the nations CIA/MI6 type group has already shut it down in the last couple of weeks. The party is aware of this, but they are going to see if they can find anything else that may have been missed. I don't want them to necessarily waste their time, so I want something to be able to be found, but I'm not quite sure what. Does anyone have any ideas for what they might be able to find?

It really depends on what it is they're looking for, but generally speaking, you'll want the party to have some additional information or context that the first group lacked, so they can make sense of something the others couldn't (and thus left behind). Stuff like:

- fragments of burned documents, where the party can fill in blanks based on what they already know
- "Hey, this is the same style dagger/poisoned dart that got thrown/shot at us in that alley!"
- a similarly designed hidden compartment to one they've found before in another hideout

Thanks for the response! This definitely gives me a launching point to try to get some stuff together! 

To add to post #2, it also depends on what exactly the national agency was looking for. Anything they didn't care about could still be useful to the players. They could have purposefully left behind anything that didn't further their goals or that was of no value to them.

Another thing to take into consideration is if other parties may be interested in that hideout after it was dismantled. Perhaps some monsters decided to move in and turn the place into a new den, bringing new treasure with them. Perhaps a rival group of adventurers had the same idea as the players, giving you the opportunity to force an encounter. Perhaps a young dragon decided to build its first lair there after leaving its parents' home. You could make an unexpected quest with this one. The young dragon could be looking for a mate and asking the players for help on the matter.

Also, the groups that raided the lair may have left something behind of value, or at least something that gives a clue about their identity.

Lol, this literally happened to me last session. Party knew a cult hideout had been scrubbed and abandoned and they went to check it out anyway. I gave them a fragment of paper with invisible ink on it (still haven't decided what will be revealed when they whip up a reagent, but the invisible ink was 100% a ploy to buy me time to think), a cult amulet they can use for future impersonation attempts, and let them battle some cranium rats that recently moved into the kitchen. 

One thing I had an NPC ally do was ask the PCs what they were hoping to find in a lair that was known to be abandoned. Gave me some ideas to vamp on while I was pulling things out of thin air as they attempted to sneak in. 

Aside from information and monsters to fight, you might let them find a couple discarded weapons/potions, a stash of fake IDs (that could be used to track down or burn aliases?), an old cipher key, some incriminating documents, maybe a trail of blood or personal effects to be used for scrying/tracking purposes...stuff like that.

They could stumble on the remains of intel like documents or a lost contact agent returning to the base without knowing it was shut down where it could be questionned. Or Messenger with a  delayed package delivery. Or neighbors having info about these ex occupants. 

All great ideas! Definitely gives me some inspiration. Thanks y'all!

I don't know where you're going from here, but some kind of evidence that your CIA/MI6 organization did some shady/questionable stuff there would be interesting. Something that makes the party wonder if they had alternative/nefarious motives.

Quote from scatterbraind >>

I don't know where you're going from here, but some kind of evidence that your CIA/MI6 organization did some shady/questionable stuff there would be interesting. Something that makes the party wonder if they had alternative/nefarious motives.

 That should be a given, what with real life agencies of the sort basically being Lawful Evil.

You can always do things like a secret room/compartment that the other agency missed, some scraps of documents that weren't taken, maybe something hidden inside that wasn't found.  Another option would be for the party to have to try to get data from the other agency. Or maybe they find a witness that the other agency hasn't picked up yet?

Merigold00Yahoo beat me to it by three minutes with the secret room or compartment idea. This agency might have just done a quick once-over so they could go on their lunch break, depending on how serious the investigators were. And maybe some evidence might've been contaminated and thus discarded, fruit of the poisonous tree and all that. What about the surrounding area, did anyone leave anything behind during an escape, or left something behind to be found by another member of this hideout (see how the Peregrin left behind his Leaf of Lórien brooch to help the Fellowship find him during his capture by the orcs)?

Every location leading from the hideout to the agency's headquarters could be home to something vital or simply interesting to know.

Part of the cipher was jammed in the copier. Er... aah....

An old cipher is folded up and wedged under a leg of a desk to stop it from wobbling. The cipher is easy to break as it was one of the first they tried. It talks of one of the first ops the cult was successful on. The incident is well known but the perpetrator was unknown, until now. This clue gives insight on the cults origin or past boss(es). The PCs can follow up from there.

There is a secret room that has vital information regarding a plot that is about to be carried out. Or maybe it's just a letter detailing some clue for them to investigate. Maybe information about a Double Agent in that spy agency, who was a little "overzealous" to try and cover up the evidence.

If the place didn't have time to confiscate their hidden information, would the attackers?

If the attackers on the base took all the info they could, then the only things left would be in secret compartments (as others have suggested), hidden, or otherwise with some sort of protection the attackers would not want to face.

If the attackers would not bother taking info from the previous base's residents, then their might be stuff all over the place. Ultimately, however, it really depends on what the attackers would've taken (as I explained above).

What are relations like between the government agency and the party?

If the agency is aware of the parties involvement with trying to track down the Cult then they might leave something tempting behind with which to scry on the party - EG an amulet with some useful power for one of the party members.

The agency might even leave behind copies of the clues they found to help the party to close in on the cult. After the party gets to the cult and wins, have the Agency sweep in with a "We'll take it from here" attitude, acting like the party did nothing and taking all the credit, to fuel animosity and prepare the next BBEG for them - the Agency themselves.

A secret room which looks like the agency missed it would be a good place for the clues to be. Give them odd clues, like "all the paper looks similar, like it was all written in the same place", or "all the ink is the same", "the door is remarkably obvious, it's surprising they didn't find it". Play to the parties ego, EG if someone is amazing at investigation then tell them the door is obvious and the Agency must be idiots to have missed it, things like that.