In some music videos, they may choose to use a narrative throughout their video. Traditionally stories consist of exposition, rising action, climax, falling action and the denouement. This is called the narrative arc. Narrative storylines tend to be linear or chronological. 

We automatically assume that there is a beginning, middle and end in a narrative. However a narrative in a song does not always run to the way we think it will. In a song there tends to be fragments of a narrative and can aid the repeatability of a promo.