Interactive Story allows for plot diversion through the use of "remembered scenes". An action can remember the current scene before calling another scene. The called scene (or scenes) can then return to the last remembered scene.
This mechanism allows for sub-plots to occur at anytime within a narrative. For example, examining an item in the inventory triggers a flashback.
Interactive Story allows for scene variations triggered by items in the inventory and by previous actions. A reader returning to a scene may encounter a change in description based on the items held in the inventory (such as a torch or lantern).