Given that Harry and his friends spend a good chunk of their time fighting folks called "Death Eaters," you probably got the memo: death is a big theme in Harry Potter and the Deathly Hallows, Part 2…and, well, pretty much all the other movies, too.
Harry's epic journey toward this showdown with Voldemort started with the death of his parents, and will end with either him or Voldemort dying—or maybe both.
See, Harry's been working hard to destroy these things called Horcruxes, which house little bits of Voldemort's soul, but he encounters some pretty massive challenges at every turn. Then he gets some pretty shocking news: when Voldemort killed his parents, Harry became a Horcrux. That's right: In order for Voldemort to die, Harry needs to die, too.
But you'll have to watch the movie (or check out the summaries above) to find out exactly what happens.
Questions About Death
What do you think goes on when Voldemort "kills" Harry?
Is it important that Harry at least believes he has to die to defeat Voldemort?
Why didn't Voldemort just try to win the Elder Wand from Snape, rather than killing him?
Why does Harry drop the Resurrection Stone right before going to let Voldemort kill him?
Chew on This
Voldemort can't defeat Harry because he was weakened from all those soul divisions and he hadn't "won" the Elder Wand—it's as simple as that.
Sure, Voldemort was weakened and using a wand that didn't work correctly for him, but we think Harry is working some special kind of magical protection when he chooses to sacrifice himself. By being willing to give everything up, he somehow gains some kind of magical protection against Voldemort's Killing Cpell.