The adaptation of J.K. Rowling's seventh and final novel comes in two installments, with the second film due out next July.
Fans may leave frustrated that they have to wait eight months for the finale. But Rowling's last book needed to be broken into two parts for the big screen, said Daniel Radcliffe, who stars as Harry.
"I was always very much in favor of it being two parts, and I think most people were, simply because we all realized there was no way you could do justice to the book and really capture the story in one film," Radcliffe told The Associated Press.
In the first six books, there was secondary action that could be cut from the movies, "themes which while exciting and while fans love them, simply don't add anything to the main thrust of the story," Radcliffe said. "In the seventh book, there is very little extraneous stuff that's not actually contributing heavily to the main plot line."
"Part 1" sends Harry and pals Hermione (Emma Watson) and Ron (Rupert Grint) outside their usual haunts at Hogwarts School of Witchcraft and Wizardry as they search for artifacts that are the key to the power of dark Lord Voldemort (Ralph Fiennes).
"It's kind of an edgy road movie where these three iconic characters, who we've always seen in this magical place called Hogwarts, are thrust out in to the big, bad world and have to fend for themselves and survive," said David Yates, who directed both parts of "Deathly Hallows" as well as the fifth and sixth "Harry Potter" films.
"As much as we love Hogwarts, we needed a fresh environment. We needed to be out of our comfort zones, definitely," Watson said
And what's Voldemort aiming to get out of all of this?
"Everyone knows, don't they? They read all the books, don't they? They all know what he's up to: world domination, total power," Fiennes said.
"Harry Potter and the Deathly Hallows: Part 2" will bring to a close one of Hollywood's most remarkable film franchises, a gambit of more than a decade by Warner Bros. to bring all of Rowling's novels to the screen before the young stars outgrew their roles.
The result will be a 20-hour saga allowing fans to watch Harry grow from a shy, neglected 11-year-old to a bold, noble young man.
"I don't think it'll take too long before these films do finish and finally come out for cinemas all over the world to be having `Harry Potter' marathons, where they just play them all back to back," Radcliffe said. "And I imagine attendance will be huge."