There were some interesting thoughts this month over at D&D Insider, a Dungeon Editorial (from Dungeon # 185) about "Dramatic Structure".
Now I've never really thought about this personally, I just sort of "do it" without any bells and whistles or fuss.
You know, theres a beginning, a middle, and an end to every adventure - but it was REALLY interesting seeing it laid out and discussed like that.
Of course an RPG is different to other Mediums, but a lot of elements are the same - Protagonists (PC's & NPC's), Antagonists (NPC's & Monsters), the Setup (Act 1 if it were a Play - in RPG terms the PC's meet an NPC in a Tavern who "hires" or "Quests" them with a task), a steady build of conflic/tension through Confrontation & Encounters (Act 2), and sorts it all out for Better (Comedy/Resolution - funny moments in a game are very important, as is your Players achieving their goals, should they repeatedly fail - you WILL lose some or possibly all, of your group) or Worse (Tragedy/Resolution/Failiure - SOMETIMES your PC's HAVE to fail, for the sake of the plot - so you HAVE a "place" for them to go in your Game World) in the Final Part of a Scenario or Story (Act 3).
I've ALWAYS found Players enjoy "Dungeon Crawls" more than any other type of Scenario, now thats not to say that I DON'T run "non" Dungeon games - I do, its just that when I hear my Players chatting/reminiscing about games - the Dungeon "elements" always seem to stick in their minds. So I like to stick to whats fun, for both my players and myself.
One of the "pitfalls" DM's find when running extensive or repeated Dungeon based Scenarios is blandness, things always seem "the same" with no real variation in plot. Now THATS where following the rules of dramatic structure REALLY come in handy.
ALWAYS (and I mean always too LoL) follow the Dramatic Structure and you really cannot go wrong, by having a fairly "rigid" structure - you actually "free" your imagination up - giving you the ability to insert more "flavour" into your Dungeon based Scenarios.
ACT I - The Setup
Whether you actually run the Setup as part of the Scenario, or its just there as "fluff" for the players so they know why their characters are intering the Dungeon - it should be rich and fully realized. Don't skimp of detail, don't skimp on information. There SHOULDN'T be a Villain in every game, but by the same token don't have endless streams of "lost artifacts" for the PC's to retrieve.
Other options could be - rescue a Kidnap Victim, a Lost Child, Deliver a Message, Bury an NPC's Remains, or even (as I did in one scenario) rescue a lost Cat.
ACT II - The "Meat" of the Story
Keep things fresh, don't be afraid to "roll" with the punches your players throw at you. I remember one game I ran, the Party were storming through my carefully planned Dungeon - Kicking in EVERY wooden door. It was boring for me, so when they moved onto Level II - SUDDENLY all the Doors were stone, and very heavy (there was one moment in a Pit room with a sliding stone door, the Players spent nearly an HOUR trying to get out of that room. Searching for Secret Panels, JUMPING up and down to activate pressure plates etc - it didn't occur to them to check if it slid LoL).
ACT III - The Resolution
Again, keep things fresh and exciting - Don't "force" the ending. If someone Dies (a PC or beloved NPC) roll with it, play up the Pathos - ONLY ON VERY RARE OCCASIONS should you Plan to kill even an NPC. It just pisses of your Players when you do. By the same token, if your "Main Villain" (if you have one) fails to die, or manages to Escape - go with that too, then you have a Plot for later on (Revenge or Track him Down) - and never EVER get pissed off when your Players kill off a Carefully Crafted Major Villain or Monster! Thats what they are there for!!!
So, there you go - just some thoughts that I find useful and might help.