World War Z (2013)

Marc Forster's adaptation kept only the title from Max Brooks's oral history, replacing its innovative multi-perspective structure with a generic Brad Pitt globe-trot. This makes it even less faithful than the #2 worst adaptation on this list, as World War Z shares only 10% of its plot with the source material. A completely rewritten third act ballooned reshoot costs, driving the budget to $190 million—40% higher than the average blockbuster's $150 million—and delivering a movie that captures none of the book's cold, journalistic terror.