Duel between Molly Weasley and Bellatrix Lestrange

During the second half of the Battle of Hogwarts, Bellatrix Lestrange nearly hit Ginny Weasley with a Killing Curse. An outraged Molly Weasley decided to take over the duel, resulting in Bellatrix's death.

Book Version
In the book, the duel is not specified, but it ended with Molly hitting Bellatrix with a curse that killed her.

Movie Version
After Bellatrix Lestrange's curse missed Ginny Weasley by an inch, Molly decided to take over the battle. Bellatrix laughed at her challenger. Molly sent a Stunning Spell at Bellatrix, but she cast a charm to protect herself. Then the two women began duelling with a series of curses, mainly the Killing Curse. After a while, Bellatrix began laughing at Molly again, but the latter was fast enough to successfully Bella with a Killing Curse. She then cast another spell which seemed to make Bellatrix look like she was falling. Molly's finishing blow blast Bella into pieces, resulting in victory.