Bellatrix Lestrange

"Potter, you cannot win against me! I was and am the Dark Lord's most loyal servant. I learned the Dark Arts from him, and I know spells of such power that you, pathetic little boy, can never hope to compete!"

- Bellatrix Lestrange, taunting Harry during the Battle of the Department of Mysteries.

Bellatrix Lestrange (née Black), also known as Bella, is a pure-blood witch and a follower of Lord Voldemort in the Harry Potter franchise. She's the quaternary antagonist in Order of the Phoenix, and the secondary antagonist in Half Blood Prince and ''Deathly Hallows. ''She is portayed by Helena Bonham Carter in the films.

Appearance
Bellatrix was described as beautiful in the pensieve, with sleek (straight), thick, shining black hair. She was tall and proud. After Azkaban, Bellatrix was still beautiful, but hollowed out.

History
Bellatrix Lestrange was born to Cygnus and Druella Black in 1951. After graduating from Hogwarts, she became one of Voldemort's most important, and possibly most sadistic, followers, known as the Death Eaters. Bellatrix was one of the few females in the group, and was the wife of Rodolphus Lestrange. She, along with her husband, was imprisoned in the wizard prison Azkaban after torturing Frank and Alice Longbottom into insanity using the Cruciatus Curse, her specialty spell.

During Voldemort's second rise to power in 1996, Bellatrix escaped along with many other Death Eaters. She later participated in the Battle of the Department of Mysteries, where she taunted Neville Longbottom and killed her cousin Sirius Black.

Bellatrix was killed by Molly Weasley during the Battle of Hogwarts on May 2, 1998.

Plot
In the films, Bellatrix serves as the quaternary antagonist in Order of the Phoenix and assumes the role of the secondary antagonist of Half-Blood Prince. She then returns to her role as the secondary antagonist in Deathly Hallows Part 1 and Deathly Hallows Part 2. She is also the secondary antagonist in the series overall due to her arguably being Voldemort's most evil, violent, and loyal supporter. Her role is expanded a bit in the films, although she does not appear in the trial scene in Harry Potter and the Goblet of Fire, with Karkaroff testifying against Barty Crouch Jr., the only Death Eater equal to Bellatrix in insanity and loyalty to Voldemort, who took part in the torture of Frank and Alice Longbottom. Bellatrix was the main torturer, as mentioned by Neville.

In Harry Potter and the Order of the Phoenix, Bellatrix was broken out of Azkaban by Voldemort and some of his Death Eaters, along with Antonin Dolohov and many other Death Eaters. Bellatrix and Lucius Malfoy later led the Death Eaters in the Department of Mysteries to take the Prophecy from Harry when Voldemort tricked him into retrieving it. Eventually, Sirius arrived with Remus Lupin, Nymphadora Tonks, Kingsley Shacklebolt, and Alastor "Mad-Eye" Moody, and he and Harry defeated Lucius and Dolohov. Bellatrix then killed Sirius with the Avada Kedavra curse, blast him into the archway and disappeared. An enraged Harry attempted to use the Cruciatus Curse on Bellatrix, but was unable to perform the spell correctly as, according to Voldemort, he had to "mean it." When Albus Dumbledore arrived to duel Voldemort, Bellatrix escaped through the fireplace.

In Harry Potter and the Half-Blood Prince, Bellatrix and her sister Narcissa Malfoy had Severus Snape make the Unbreakable Vow to protect Draco Malfoy and kill Dumbledore should Draco fail to do so. She also burned down the Burrow at one point, although it was later rebuilt afterward. After Snape killed Dumbledore, Bellatrix attacked Hogwart's Great Hall and Hagrid's hut, setting it on fire despite it being made of stone.

In Harry Potter and the Deathly Hallows, Part 1, Bellatrix wanted to kill Harry, but Voldemort said that he must be the one to kill him. At some point before his death, knowing that Voldemort wished to possess the belongings of the four founders of Hogwarts, Dumbledore gave a fake Sword of Gryffindor to Snape, who gave it to Voldemort, who entrusted it to Bellatrix, who kept it in her high-security vault at the wizards' bank Gringotts.

When Snatchers, led by Scabior, took Harry, Ron Weasley, and Hermione Granger to Malfoy Manor, Bellatrix saw the Sword of Gryffindor and thought that Harry had broken into her vault. Furious that the Sword of Gryffinor are in the trio's hands, she stunned whole snatchers present, and planned to kill them later. Bellatrix proceed to tortured Hermione for information, and the wrathful witch carving the word "Mudblood" into her arm. Then she questioned Griphook about the sword and decided to kill Hermione; however, Ron disarmed her before she could. Later, Dobby sent a chandelier crashing down toward Bellatrix just as she uses her dark mark to summon Voldemort, who avoided it, and as Dobby disapparated with Harry, Ron, Hermione, and Griphook, Bellatrix threw her knife at him, killing him.

Hermione later disguised herself as Bellatrix to get into her vault in Gringotts, which was guarded by a dragon; Bellatrix never knew of this. It is presumed that, in Harry Potter and the Deathly Hallows Part 2, Bellatrix was the one who killed Tonks as in the book, since Tonks's death is never shown on-screen.

During the final battle, she fires a Killing Curse on Ginny, but fails and only enciting Molly Weasley's fury. Molly fights Bellatrix in a rage, and in the end, Molly emerges victorious. Bellatrix never thought that Molly would defeat and kill her and avenging Sirius, Tonks and Dobby.

Trivia

 * During the filming of Harry Potter and the Deathly Hallows, Helena Bonham Carter also filmed The King's Speech. She was glad about this because at those moments, she could spare her voice and didn't have to scream all day.
 * Bellatrix's death was the last scene that Helena Bonham Carter filmed for Harry Potter.
 * Bellatrix was also released in many Lego Harry Potter sets as a Lego minifigure.
 * In movie, Bellatrix's last battle against Molly until her death and moments where she corners Ginny was depicted very different, though in both cases, she start off corners Ginny with Killing Curse:
 * In the movie, Ginny was cornered after using an unknown very powerful shield charm that powerful enough to dissipates Killing Curse blast before it hit her, but severely weaken her from continuing the battle, in which Molly took over the fight so Ginny could recover. In the book, Ginny was cornered along with Hermione and Luna Lovegood and survived the Killing Curse simply by avoid it an inch.
 * Bellatrix's battle was more intense in the book, as the book describes ground below them cracks and hotter, shows that spells that they used to attack each other are more destructive than in the movie. Bellatrix even mocks Molly over Fred's death, which was her very fatal mistake due to being overestimate her opponent.
 * Bellatrix's death was different, as while in the movie her body shown destroyed after being petrified by Molly, whom later blasted and fell into pieces, her body was remain intact instead in the book as Molly merely blast her in the chest with a curse that presumably damage her heart, causes her death with a frozen smile.