This is when a Novelization of a work (usually a film) arrives on store shelves before the work's own debut, resulting in Spoilers to those who read it. It can happen in any media, and is increasingly common in big-budget titles. This, obviously, does not apply to cases where the original work is a book series itself (e.g. Harry Potter) and receives a re-release right before its film adaptation hits the box office. (Unless the novelization is specifically based on the adaptation, instead of the original source.) Subtrope of Adaptation First. See also: Sequel First.