Random Adventure Generator

ThemeEspionage
Espionage adventures are active, grim scenarios involving spying and perhaps other cloak-and-dagger deeds such as assassination or rescue.
GoalProtect Endangered NPC(s)
One or more NPCs are in danger, and the characters must protect them. They might be doing this for a reward, or because one or more of the NPCs is a friend or relative of the character. You need to decide what the characters are protecting the NPCs from. The NPC might be a wealthy or powerful person being sought by assassins or kidnappers. The NPC might be a whole village of peasants who are being terrorized by a bandit chieftan.
Story HookLegend and Rumor
In this classic story hook, the hero stumbles across some new or long-forgotten knowledge that promises great treasure or gain.
PlotA-B-C Quest
This is an epic sort of plot. In it, the heros are given (or undertake) a task to perform: The taking of a city, the rescue of an innocent, the destruction of a monster, the creation of a magical item, the defeat of a Master Villain, etc. But the path to victory is not a simple one. To get to their goal, Event A, they find that they must first accomplish some other task -- Event B. But when they undertake the task of accomplishing Event B, they find that they must first accomplish Event C. This goes on for several encounters, until the heroes accomplish all the obstacle events which prevent them from returning to Event A, their original goal.
ClimaxPrevented Deed
Here, the heroes have been defeated -- captured by the Master Villain, or so thoroughly cut up by his minions that all believe them to be dead. And the heroes have learned, from the bragging of the villain, loose talk of his minions, or examination of clues, what is the crucial event of his master plan. In any case, the battered and bruised heroes must race to this site and have their final confrontation with the villain, bursting in on him and his minions just as the knife or final word or key is poised, and prevent the awful deed from taking place -- and, incidentally, defeat the master villain and minions who beat them previously.
General SettingOn the Road
Most of the adventure takes place on the road, as the heroes are travelling from place to place. This is especially good for adventures where heroes are investigating a wide-ranging mystery, are part of a caravan, or are being pursued by loathesome villains.
Specific Setting ILost City
This is the remnant of some lost civilization or expedition, still thriving in some forgotten corner of the world. Remnants of lost civilizations can even inhabit cavern systems beneath campaign cities, preying on the above-worlders for their goods, slaves, and sacrifices.
Specific Setting IIClassic Dungeon
This would be the standard monster-filled labyrinth; perhaps it's a nesting ground for the master villain's monster troops.
Master VillainZealot
This villain is like the Conqueror, but he's not trying to conquer to own; he's trying to purge the world of something he feels is pure evil (another religion, a human, demi-human, or nonhuman race of sentient beings, a custom). He operates just like the Conqueror, enslaving or killing all those who belong to the "wrong" race or philosophy.
Minor Villain IChief Assassin
The Chief Assassin is the favorite killer of the Master Villain. The Assassin works mostly in the field, first killing witnesses who might prove harmful to his master, then zeroing in on the player-characters. He usually meets his end before the adventure's climax, but he may taken one of the heroes down with him.
Minor Villain IIHard-Eyed Advisor
This is the sort of villain whom the heroes see in the Master Villain's throne room. He's hard-eyed and scary; life means nothing to him and he enjoys killing. He's also a good advisor to his master.
Ally/NeutralMerry Minstrel
This character follows the heroes in order that he might find inspiration for his song and storytelling. He can't be shut up; he sings all the day long and into the night, is a showoff before crowds, and is far too noisy for a party trying to remain unobserved.
Monster EncounterNoble Beast
With this encounter, the heroes find that they have to capture -- but not injure -- some sort of powerful, noble beast in order to accomplish their mission. For instance, to reach a mountain-top aerie, they must capture pegasi and ride them up to their enemy.
Character EncounterInquisitive Official
Some local authority has noticed the characters' presence and it makes her curious. She snoops around asking questions all the time. She may be a city guardsman or special agent of the ruler, but (functionally) she's a police lieutenant, asking the rong questions at the wrong time; the heroes have to work around her, sneaking where normally they'd be able to work in the open.
DeathtrapColiseum
If it's appropriate, you can have the heroes captured by the local authorities -- particularly when they're in an exotic land, lost world, or whatever -- and have them armed with gladiatorial gear and dropped into a coliseum for the entertainment of the locals. (Note that this works much better with fighting-type heroes than spellcasters.)
ChaseAerial
The heroes could be riding pegasi or friendly griffons or allied great eagles; the villains could be carried aloft by gargoyles or demons. The prospect of taking a mile-long fall if one's mount is hit is a very daunting and challenging one for the hero.
Omen/ProphesyBirthmark
One of the heroes has a birthmark that pertains to the adventure in some way. He may have a birthmark identical to some NPC -- for instance, some person endangered by the Master Villain. This mystery can give the hero his reason to become involved. Alternatively, his birthmark may mark him as a hero fulfilling some ancient prophecy.
Secret WeaknessElement
The Master Villain can be banished, dispelled, killed, or otherwise defeated by some of element or item. The Master Villain tries to get rid of all the examples of this element in his vicinity; he doesn't let his minions carry it or bring it into his presence. But he's not stupid; he doesn't announce to the world what his weakness is. He tries to hide his concern within another command. If he's allergic to red roses, for instance, he orders all "things of beauty" destroyed within miles of his abode.
Special ConditionTime Limit
Finally, the most obvious condition to place on an adventure is to give it a time limit. If the Master Villain is going to conclude his evil spell in only three days, and his citadel is three hard days' riding away, then the heroes are going to be on the go all throughout the adventure -- with little time to rest, plan, gather allies, or anything except get to where they're going.
Moral QuandryHonor Quandry
You want to use this on the character with the most strongly developed sense of personal honor -- someone who has lived all his life by a strict code. Toward the end of the adventure, this character realizes that the best way to defeat the Master Villain is a violation of that code. For instance, the character might be a paladin, who discovers that the only possible way for the heroes to defeat the Master Villain is to sneak up on him and stab him in the back.
Red HerringLying Rumor
This is the worst and most useful type of red herring -- the interesting rumor which just happens to be false. In adventures of this sort, the best Lying Rumor concerns the Master Villain; it gives the heroes some "important" information about him which later turns out to be useless.
Cruel TrickMission is a Ruse
In the course of their adventuring, the heroes discover they have been tricked into performing a mission which helps the Master Villain.

Based upon tables from the Dungeon Master's Design Kit by TSR, Inc.