The 5th Wave is a young adult science fiction novel written by American author Rick Yancey.

The story follows 16-year-old Cassie Sullivan as she tries to survive in a world devastated by waves of alien invasions that decimated the Earth's population.

An alien invasion consisting of four "waves" of increasing severity has resulted in the death of most of the human population, with survivors scattered in mostly rural areas.

While the army purports to be fighting the others, they soon discover that they have been tricked into targeting fellow human survivors.

Critical reception of the book was fairly positive, although some reviewers noted an overreliance on genre tropes.

[1][2] Justin Cronin of The New York Times wrote that while "just about everything here is borrowed from one venerable pop culture source or another", it was a "rip-roaring setup, and as the bodies accumulate, the pages turn themselves.

It was directed by J Blakeson, with a screenplay by Susannah Grant, Akiva Goldsman, and Jeff Pinkner.