The Dynamic Adventures System presents a mechanic to be used with any setting. It is a mechanic which is meant to play RPGs with a group of people, but unlike traditional RPGs there are no dice rolls and control of your character isn't always 100% yours. DAS presents a game of collaborative storytelling. There is still a Game Master as in traditional RPGs, but their role in the game is lessened, rather than control every NPC this is left largely to the imagination of the players. The storyteller sets the scene, lets a player run with it and influence the story subtely.
Characters are made of a series of traits, which represent physical, mental and social capabilities, skills and personality traits. These traits are both positive and negative, but all equally important. Likewise every NPC has a few traits (notably less than PCs unless they are a major character) and scenes and stories also have traits.
Traits are used for two things, first of all to gain control of a scene. Once the GM has set out the parameters of the scene, the players 'bid' their appropriate traits in order to gain control of the scene. These can be both positive and negative traits (although negative traits then get given to the GM to use as they please.) The player who bids the most traits wins the bid and gains control of the scene, describing it as they please, keeping in mind the traits and personalities of all the characters.
The control isn't 100% however. Other players, including the GM, can spend their appropriate traits in order to influence the story as it progresses. The 'tweak' has to occur when the event is about to happen. A player can't retroactively tweak something that happened ten seconds ago. The GM spends the NPCs tweaks when appropriate but also has a series of Scene Traits that they can employ as well, these can be used at any time and represent the advantage of the opposition, particularily dramatic scenes or something unseen working for or against the players.
This applies to all scenes, whether action, mental or socially orientated. A subtle different occurs in a primarily social based scene. The main player still directs the scene as always but he opens up the conversation(s) to other players by giving them openings. The players say their characters peice and the main player states how the other party or parties react. A player may still tweak their dialouge in order to get more favourable results (or less favourable if employing a negative trait.) This way players never feel as though their character's opinionz, thoughts and feelings are reduced to someone elses imagination, allowing them to roleplay.