I've talked a lot recently about how to structure an extended investigation. An example of one is in my PF1 adventure, A Lucky Morning (which you can get right here).

To be more than a little bit spoilery, that adventure is about an evil necromancer getting revenge on a former adventuring group that shunned him. He's killing off the group's former members, and he doesn't care who he kills along the way. The adventure begins with the heroes waking up in the private rooms of a big inn, coming downstairs, and seeing that everyone else in the inn has been killed in a strange way. They've all been killed by a wraith, though that isn't obvious right away. An investigation begins!

There are two "must" clues here among the dead:

1) A pair of ex-adventurers (the bard and the barbarian) have a drink ticket to the bar they normally frequent with their former adventuring companions. Getting this clue requires "Environment Interaction" (as I described the term in my last post).

2) A prospective thief is in town to interview with a third member of the former adventuring group (the thief). Getting this clue is requires a successful "Character Skill."

There are lots of "might" clues here:

1) The heroes can learn that a wraith (or something akin to one) killed everyone here. Getting this clue requires "Character Skills."

2) Dead dockworkers lead to an oracle by the docks; getting this clue requires "Character Skills." 

3) There's a sign indicating that the attack was a personal vendetta. This is an "It's Just There" clue.

4) Some clues indicate the timing of the attack and that a desperate but one-sided fight was involved. Some of these are "Environment Interaction" clues, but others are "It's Just There."

The two "must" clues lead to their own separate acts in the adventure, as does one of the "might" clues. I also included another act about what happens if the heroes do nothing--such as running to get the town watch the instant they see the dead people and don't investigate.

Must #1: Following up on the prospective thief leads the heroes to a safe house for the town thieves' guild. They can engage in some "Character Skills" or "Environment Interaction" to find that the leader of the thieves' guild, the thief ex-adventurer, has been killed just like everyone in the inn. This is ultimately a dead end, but it puts some of the plan into clearer view.

Must #2: Following up on the ex-adventurers' tavern results in "A Fight," but "Environment Interaction" uncovers a big picture of all five ex-adventurers together and hints that someone's getting revenge on them all. This is another "must" clue, as it's how the heroes learn that there's another member unaccounted for (the party's sorcerer); seeking her out leads to the linear chain of 3 acts that concludes the adventure.

Might #1: The dockworker's "might" clue leads to a different act, too, because the heroes can get information that a wraith is involved AND gain a lead to the ex-adventurers' bar requires more "Character Skills," but if the heroes are polite, this is practically "Environment Interaction." I put this in there to make sure that players who went chasing off on this wrong track could be nudged back to the main plot.

Do Nothing: If the heroes don't do any investigating, or if they return to the scene of the crime after leaving it, the town watch is there. They take the heroes to the watch station automatically, as an "It's Just There" clue. While in the watch station, the heroes narrowly avoid another wraith attack that kills the watch captain (the fighter of the former adventuring group). They discover this death with some "Character Skills," but if they just fail at those, "It's Just There" gives them the clue anyway (to avoid a skill wall that traps the heroes in the watch station for good!). 

So it's likely that the heroes will do lots of running around, but will land on the necessity of finding the retired sorcerer. In case this isn't crystal clear, though, I've included an encounter where the necromancer tries to kill the heroes in a straightforward trap. There's also a limerick involved; I'm not sure what I was thinking. This is technically "A Fight," as traps are included under that header, and it points the heroes toward the sorcerer. If they didn't know to go there, they learn it; if they already knew to go there, it confirms what they know and assures them they're on a fruitful path.

The adventure concludes with a dramatic combat against the villain, but there's a lot of investigation to get to that point. The fight is the payoff for the heroes discovering what's going on and intentionally inserting themselves into the evil plan to prevent it.

This investigation adventure isn't perfect; I knew I had too many "skill walls" when I wrote it, and my solution was the suboptimal trick of setting some target numbers crazy low rather than just giving the clue without a check. But this adventure contains a lot of interconnectedness that means no group is going to play it the same way, and that's a sign of a well-connected extended investigation.

Robust investigations take some work, but they're worth it!