In the study of literature and the analysis of plot, falling action is what occurs directly after the climax. Falling action occurs before and leads to the denouement.
As such, falling action comes as a direct result of the climax of the plot and expands on whatever comes from the climax. For example, if the climax involves the hero winning a car race, the falling action is the victory lap and all the accolades.
Falling action is part of a system of looking at literary plot structures devised by Gustav Freytag, a 19th century German novelist who saw similarities in the structures of stories and novels.