Bellatrix Lestrange, born Bellatrix Black, was a Pure-blood Dark witch and follower of Voldemort. Born to the House of Black as the oldest of three daughters, she grew up a fanatical Pure-blood supremacist and was one of his most sadistic and cruel followers.

Bellatrix was born in 1951 to Cygnus Black III and Druella Black (née Rosier). She had two younger sisters, Andromeda and Narcissa. She attended Hogwarts School and was sorted into Slytherin, and was very close to her sisters. She became deeply involved in Dark magic, and joined a group of aspiring Death Eaters within Slytherin House, alongside Severus Snape, Rodolphus Lestrange, and others.

When Andromeda married Ted Tonks, a Muggle-born, after graduating, Bellatrix cut off contact with her and Andromeda was disowned. Bellatrix married Rodolphus Lestrange, a fellow Slytherin and follower of Lord Voldemort, but they never showed any love or interest in him.

Bellatrix partook in the First Wizarding War as a Death Eater and avid supporter of the Dark Lord. After the Dark Lord fell during the attack on the Potters, Bellatrix, Rodolphus, his brother Rabastan, and another Death Eater, Barty Crouch Jnr., attacked Frank and Alice Longbottom and tortured them for information on the Dark Lord's fate and drove them insane.

Bellatrix and her compatriots were arrested and put in front of the Council of Magical Law, where Bellatrix proudly proclaimed her loyalty to Voldemort, and was sentenced to life in Azkaban for her crimes.

In January 1996, 6 months after Voldemort's return to power, Bellatrix and nine Death Eaters were broken out of Azkaban by Voldemort as a reward for their loyalty. Bellatrix was part of the Death Eater team sent to the Department of Mysteries to obtain the prophecy. Bellatrix tortured Neville Longbottom with the Cruciatus Curse, and later defeated her niece, Nymphadora Tonks, and hit her cousin, Siris Black, with a spell that knocked him backwards into the Veil in the Death Chamber, killing him.

Sometime after the Battle of the Department of Mysteries, Bellatrix fell pregnant with Voldemort's daughter, Delphini, who was raised by the loyal Rowle family.

In March 1998, Harry Potter, Hermione Granger, and Ron Weasley were attacked and captured by Snatchers and brought to Malfoy Manor. Bellatrix tortured Hermione for information on how the trio obtained the Sword of Gryffindor. Dobby protected the trio and aided their escape, but was killed by Bellatrix for his efforts.

Bellatrix took part in the Battle of Hogwarts on 2nd May 1998. The Death Eater forces continued the fight into its second phase; Bellatrix was the last Death Eater standing, and duelled Hermione Granger, Ginny Weasley, and Luna Lovegood simultaneously. After barely missing Ginny with a Killing Curse, both Harry and Molly Weasley began to attack Bellatrix. Bellatrix was hit in the chest with a fatal Curse from Molly Weasley and died. Shortly after, Harry was revealed to have survived the Killing Curse for a second time, and defeated Voldemort for good.