The rising action of a plot is the series of events that build up and create tension and suspense. This tension is a result of the basic conflict that exists and makes the story interesting.
The rising action can be identified as the ingredients that complicate matters in a plot. We will see rising action in any story, from a complex novel to a simple children's story. For example, the rising action in The Three Little Pigs takes place as the pigs set out on their own and begin to make their own decisions.
We know that the first two individuals are asking for trouble when they choose unsound materials to build houses. These decisions (along with the wolf who lurks in the background) create an air of tension that mounts as the story progresses. Things get more and more exiting and tense each time the wolf blows down a house! The action builds toward an ultimate showdown between pigs and wolf.
In literature, the rising action comprises all the decisions, background circumstances, and character flaws that combine to create twists and turns toward a climax.