Which Harry Potter book was split into two films for its movie adaptation?

Harry Potter and the Deathly Hallows was split into two films for its movie adaptation.

The final novel in J.K. Rowling’s seven-book series was adapted as Harry Potter and the Deathly Hallows – Part 1, released in 2010, and Part 2, released in 2011. The two-part approach allowed the filmmakers to retain more plot and character material from the longest and most climactic book.

This decision produced eight films from seven novels. The other six books each received one feature-film adaptation, while the seventh book received two. The two films follow Harry, Ron and Hermione as they search for Horcruxes and prepare for the final confrontation with Voldemort.

The split was announced during production rather than reflecting two separate Rowling novels. Deathly Hallows is therefore one book, even though audiences encountered its film story in two theatrical releases.