Scenario building: from cliche to complexity!

So. Here are eight deeply unoriginal D&D scenario concepts:

1. The PCs are hired as caravan guards to protect a caravan in case bandits attack. (Spoiler: they do!)
2. The PCs are hired to drive off a tribe of goblins who are raiding nearby villages.
3. The PCs have to stop an evil cult before they summon a horrible demon.
4. The PCs have to recover some kind of magic item from an ancient crypt.
5. The PCs have to hunt down an evil wizard who is doing evil magic stuff in an old ruin nearby.
6. The PCs decide to hunt down a wanted outlaw for the bounty on his head.
7. The PCs have to rescue some guy who's been captured by a band of cave-dwelling monsters.
8. The PCs have heard of treasure in an ancient ruin and decide to loot it. 

There's no reason why any of these can't be the basis for a perfectly good session - it's all in the execution, after all - but the concept won't be doing much of the work for you. Each of them implies a completely linear structure - save the dude, find the thing, stop the ritual, kill the baddies - with little if any room for complexity or player freedom. But let's start pairing them up, turning them into three-sided scenarios:

1. The PCs are hired to protect a caravan in case bandits attack. The roads are also being preyed upon by goblins, who are raiding nearby villages. The bandits and the goblins are engaged in a turf war over whose territory this is, and hate each other bitterly. 
2. The PCs have to stop an evil cult before they summon a horrible demon. A magical item rumoured to be buried in a haunted crypt nearby is said to have the power to counteract their black magic - but the cult also knows about the crypt, and is plotting to seize the magic items hidden within it for themselves. 
3. The PCs have to hunt down an evil wizard who is doing evil magic stuff in an old ruin nearby. The ruins are said to be riddled with ancient secret tunnels, which could be a major asset in any assault on the wizard's lair; but the only man who knows the way into them is a wanted outlaw who once used the ruins as a hideout, and is now lurking somewhere in the woods on account of the huge bounty placed upon his head.
4. The PCs have to rescue some guy who's been captured by a band of cave-dwelling monsters. The caverns in which they dwell are also filled with bizarre ruins built by some ancient subterranean race, of which these monsters may, in fact, be the degenerate descendants; the ruins are said to be rich in treasure, but also to be fearsomely dangerous to explorers.

These are a bit better, because they each introduce another element, raising the scenarios above the level of a simple smash-and-grab or search-and-destroy mission. Crucially, they each introduce an extra element of PC choice. 'Do you want to delve into the ruins for treasure or not?' isn't really a choice; if that's tonight's game, then that's what you're all going to do. But 'Do we keep pushing deeper into the ruins, despite the escalating danger, or do we focus on finding the captive and getting him out alive?' at least has the potential to be a real decision. 

Let's keep going:

1: The PCs are hired to protect a caravan in case bandits attack. The roads are also being preyed upon by goblins, who are raiding nearby villages. The bandits and the goblins are engaged in a turf war over whose territory this is, and hate each other bitterly. Unbeknownst to either faction, the caravan is in fact delivering ceremonial supplies to an evil cult which dwells nearby, and which plans to use them to help in their ritual to summon a horrible demon. A magical item rumoured to be buried in a haunted crypt nearby is said to have the power to counteract their black magic - but the cult also knows about the crypt, and is plotting to seize the magic items hidden within it for themselves. The goblins and the bandits are no keener on being eaten by demons than anyone else, and would happily assist the PCs in foiling the ritual if they knew about it, but their hatred of each other is so great that even under these circumstances they will refuse to work with each other.

2: The PCs have to hunt down an evil wizard who is doing evil magic stuff in an old ruin nearby. The ruins are said to be riddled with ancient secret tunnels, which could be a major asset in any assault on the wizard's lair; but the only man who knows the way into them is a wanted outlaw who once used the ruins as a hideout. Until recently he was lurking in the woods on account of the huge bounty placed upon his head, but a rockslide has exposed the entrance to a cavern system full of ruins, inhabited by cave-dwelling monsters - presumably the degenerate descendants of the creatures which built the ruins in the first place. The outlaw went to investigate the caves, lured by rumours of the treasures within, but was captured by their inhabitants and is going to be eaten at an upcoming feast, much to the consternation of the other members of his gang. Many other treasures rest down there in the ruins, some of which the evil wizard is very keen to obtain. 

Now we're getting somewhere. Multiple factions with conflicting agendas, multiple adventure sites, groups who can easily act as either allies or antagonists depending on the choices made by the PCs, real questions about what to do about the various situations - after rescuing the outlaw from the cave-monsters, and working with him to defeat the wizards, are they really going to have the heart to hand him over to the authorities for the price on his head? - and so on. But let's just go one step further, and combine all eight:

• The PCs are hired to protect a caravan in case bandits attack. The roads are also being preyed upon by goblins, who are raiding nearby villages. The bandits and the goblins are engaged in a turf war over whose territory this is, and hate each other bitterly. 
• Unbeknownst to either faction, or to the caravan's owners, the caravan is in fact delivering ceremonial supplies to an evil cult which dwells nearby, and which plans to use them to help in their ritual to summon a horrible demon which will devour everything for miles.
• A magical item rumoured to be buried in a haunted crypt nearby is said to have the power to counteract the cult's black magic - but the cult also knows about the crypt, and is plotting to seize the magic items hidden within it for themselves. 
• The goblins and the bandits are no keener on being eaten by demons than anyone else, and would happily assist the PCs in foiling the ritual if they knew about it, but their hatred of each other is so great that even under these circumstances they will refuse to work with each other.
• The man who is sending the supplies on the caravan to the cult is an evil wizard, sympathetic to their crazy agenda, who lives in an old ruin at the other end of the area which the bandits and goblins are fighting over. 
• The ruins that the wizard lives in are said to be riddled with ancient secret tunnels, which could be a major asset in any assault on his lair; but the only man who knows the way into them is a wanted outlaw who once used the ruins as a hideout, and who is now one of the leading members of the bandit gang. The local authorities have placed a huge bounty on his head.
• A recent rockslide (actually triggered by the early stages of the cult's ritual) has exposed the entrance to a nearby cavern system full of ruins, inhabited by cave-dwelling monsters - presumably the degenerate descendants of the creatures which built the ruins in the first place. 
• Local legends describe how these ruins were sealed beneath the earth by a local hero - the same hero who is buried in the haunted crypt which the cultists are looking for. The inhabitants of the ruins worship the same monster-god as the cultists - indeed, the cult was originally founded by a handful of them which were stranded on the surface when their city was first sealed away.
• The same legends emphasise that the cave-dwellers possessed many marvellous treasures. These legends led the outlaw to investigate the caves when they were first exposed, but he was captured by their inhabitants and is going to be eaten at an upcoming feast, much to the consternation of the other members of his gang. 
• The evil wizard is also keen to obtain some of the artifacts hidden in the ruins, and is so eager to obtain the ancient forbidden knowledge they contain that he'd even sell out the cult to get hold of it. (He's not a true believer: he just likes the gold they pay him and is aggressively indifferent to whether everyone else in the area gets eaten by demons or not.)

Now that's an adventure that might be worth playing. There are eight factions - the local authorities, the caravan and its owners, the bandits, the goblins, the cultists, the wizard, the cave-monsters, and the undead in the haunted crypt - all with their own conflicting agendas. There are eight different possible objectives to address - deal with the goblins, deal with the bandits, do something about the cave monsters, stop the ritual, deal with the wizard, loot the crypt, loot the ruins, get the bounty on the outlaw's head - all of which are interlinked in such a fashion that the same factors which make it easier to achieve some will make it harder to achieve others. There are six different encounter areas - wizard's ruins, goblin lair, bandit camp, cult base, caverns, crypt - at least some of which are likely to be dealt with socially rather than violently, although exactly which ones will be entirely up to the PCs. There's an interlinked backstory which connects all this stuff together. And there's enough raw stuff to do to keep most groups busy for weeks on end. 

The point of this exercise is to emphasise that even the most basic, cliched adventure material can be built up into something worth playing if you just keep adding it up. None of the ideas here are clever or original, but if you string enough of them together they can become more than the sum of their parts. In fact, I'd much rather play the adventure I've outlined above than an apparently 'original' and 'imaginative' adventure which actually just boils down to 'kill some [monsters] in a [place]'. The trick, as I've emphasised, is to keep building in connections. 'Here is a cave with some orcs, and here is a cave with some goblins' isn't twice as good as just 'here is a cave with some orcs'; in fact, it's likely to be twice as tedious. But 'here is a cave with some orcs, and here is a cave with some goblins whom the orcs are trying to convert to their new religion, with mixed success' - that's got some added value to it.

The best thing about this method is that it's easy. Going from my eight cliches to my one big adventure took me about half an hour. At no point did I have to come up with any genuinely original ideas. And yet I'm confident that the scenario I've outlined above would be pretty fun to play in, simply because it's got so many moving parts to tinker with.

So if all you can come up with is boring ideas for next week's game, don't despair. Just keep coming up with them, and keep joining them together, until you have something worth running!