A spoiler is a summary or description of a narrative (or part of a narrative) that relates plot elements not revealed early in the narrative itself. Moreover, because enjoyment of a narrative sometimes depends upon the dramatic tension and suspense which undergird it, this early revelation of plot elements can "spoil" the enjoyment of surprise that viewers/readers of the narrative may have otherwise have experienced: Eg. The revelation that Indiana Jones is Mutt Williams' biological father in Indiana Jones and the Kingdom of the Crystal Skull.