So about a week ago I read an article on one of the other blogs I frequent World Builder Blog where they talked about the benefits of tony dungeons that can be run in a single session. This eventually got me searching where I found on Roleplaytips.com the Five Room Model. The basics to these is you have a handful of scenes all showcasing a different aspect of the game to give character type a chances to shine and giving a complete experience in a single session.
While I love these ideas, I don't tend to actually do dungeons that often, but I DO run episodic adventures where I try to have a single episode run for a 2-4 hours depending on the system. I've already talked about the advantages of the 5 Act Structure for adventure design here. While I still stand by the 5 acts for an over arching story I actually think fusing the two would make for a five session story arch where each adventure can stand on it's own as well.
To break it down for people who don't like looking and cross referencing articles I'm gonna break it down then go over my tweaks.
The 5 Act Structure:
2. Rising Threat
4. The Hunt, Settling the Score, Clean Up, or Righting Wrongs
5. Final Round
The 5 Room Model:
1. Entrance & Guardian
2. Puzzle or Roleplaying
3. Trick or Setback
4. Climax, Big Battle, or Conflict
5. Reward, Revelation, or Plot Twist
Now from an adventure design the 5 room Method really needs a step 0 of an Introduction. The method is great at designing a series of scenes to challenge players when they have to get to or in somewhere, but it doesn't cover why they are doing it. This is easy enough though as it's simply figuring out what you want them to need to get done and who will ask them to do it. In fact after the first act the Room 5: Reward/Plot Twist can act as the introduction leading the group to the following act. In that way one thing you should remember is to now let the final portion of any act (except act 5) to wrap up all the loose ends.
How to make it work:
So as with any tool for writing you have to bring the ideas. I do strongly suggest reading my write up on the 5 act structure as I'm not going to go into much more detail than the break down of what the structure is. If you notice act four has a lot of different options. That's actually because thanks to player choice what they do leading up to then will determine what act four will look like. If your the kind of person that wants your story completely written before even running session one then you'll probably want to write an adventure for each of those options to cover your bases. Yes it means not all of your work will be seen, but as a GM you need to get used to that fact.
Now as for writing the story it's pretty simple if you already have an idea. Basically jot down the simplest description of what you want each act to do such as "Introduction: Hired for a simple job that turns into more. Rising Threat: The mystery unfolds showing the whole city is in danger. Climax: Get who's behind these problems for a final show down. Act 4: TBA. Finale: One last fight."
These are your themes for each adventure. You take that theme and fill out five scenes to tell a simple story. The story can actually be pretty simple from story to story as the depth gets built in how they flow together into a bigger picture. Finally like I said use room 5 at the end of each act to function as a hook for the next act.
This might sound a bit railroad-ish but the beauty of the five room system is that if the players want to try a different avenue let them and use the concept of a room they haven't done yet. Like if they don't want to take a "Guardian" head let them come up with a clever role playing or puzzle solution to get around it. Then just add a guardian before the final climax. Heck with there being five full adventures feel free to let them skip a room every so often if they find a work around or if you find they really enjoy one type of room over the others then add more of that kind of room. Still try and keep things varied and try to only have one climax per adventure (or else it isn't a climax).
Once you get the formula down feel free to toy with it from time to time. If anything this will help adventures from becoming predictable.
Bonus Notes: Trilogies & Plot Points
You can actually take this five adventure campaign and then have it funtion as the first act in an even bigger story. With this I would only suggest the first three acts. By doing this you basically do what most film trilogies do and make a fifteen adventure campaign with session level stories, smaller story arches, and an over arching story. This is a lot of depth and layering so I only suggest this once you have a bit of adventure writing under your belt.
Savage Worlds writes there campaigns in a way that I love. They call it "Plot Points" and basically there are adventures that are important to the over arching story, but they don't have to be one afte rthe other. With this you can put filler adventure in between to stretch out your campaign and not make everything feel like it's just following a story you can't avoid. With this you can make your room five hook more vague and reveal just a bit more information, but not directly tell the players where the next act is. Instead you fill in a few stand alone adventures before they pick up the trail of the main story again.