Imperial debacles, heroic last stands, the valiant defence of an island, arduous desert crossings and a deadly hunt with the PCs as prey, not predator can all be found in The Variscan War, a mini-campaign (25-40hrs) for medium-high level characters.
The evil mage Zarakoth is dead, but with his death the world has gone mad. The aging characters are confronted on all sides by rot, death and decay whilst around them the world regresses rapidly to the stone age. Furthermore, Zarakoth seems to have miraculously not died - and to be more powerful than ever.
The master thief Slith could steal a ring from the finger of an elf or the crown at a king’s coronation. He had stolen the great jewelled idol from the Temple of Imor at the climax of the Festival of Summer. Stealing the Ruby Sceptre from the archmage Bryseis should have posed no trouble to a thief of Slith’s talents. It didn’t: it was only afterwards that the trouble started.
Sometimes, just sometimes, the best response isn’t to go for your sword first and ask questions afterwards.
Most advenurers have been forced to do a stint as caravan guards at some point in their career, just to see them through hard times. One would hope that they’d learned enough from the experience to pull off a successful raid themselves. The only catch - they mustn’t kill anybody.
A plague has hit the local area.
In humans it affects only the most vulnerable, the children and the very old, and even than it's little more than a summer cold. 24 hours of sniffles and then it's gone, barely noticeable really.
To sheep however it is fatal and the whole economy of the area is in serious trouble. If this keeps up the area could well be facing famine.
Somebody (enter the PCs) must find the rare herbs needed to make a cure.