The Harry Potter reunion special has been very well-received by fans thanks to the nostalgia of seeing the cast together again in Hogwarts and for the fun behind-the-scenes stories they shared, including that many of Bellatrix Lestrange’s scenes were improvised, proving why she’s one of Harry Potter’s greatest characters. Back in 1997, readers were introduced to the Wizarding World in J.K. Rowling’s debut novel Harry Potter and the Philosopher’s Stone, the first entry in a series of seven novels that became a big pop culture phenomenon and made way for a media franchise that continues to be quite popular.

The Harry Potter series tells the story of the title character, known in the Wizarding World as “The Boy Who Lived”, and his battle against Lord Voldemort, the darkest wizard of all who failed to kill Harry when he was a baby. The success of the Harry Potter novels was such that it didn’t take long for them to be adapted to the big screen, and so the Harry Potter saga arrived between 2001 and 2011 (with Harry Potter and the Deathly Hallows being divided into two movies). The movies not only expanded the books’ fanbase but also allowed fans to have a clearer image of the characters and their personalities, and one that stood out for her unpredictability, craziness, and more is Bellatrix Lestrange (Helena Bonham Carter).

Related: How Bellatrix Lestrange Is Different In The Harry Potter Books

Bellatrix Lestrange was first mentioned in Harry Potter and the Goblet of Fire, when it was revealed that she was part of the group of Death Eaters that tortured Neville Longbottom’s parents, and thus was sent to Azkaban. Bellatrix made her proper debut in Harry Potter and the Order of the Phoenix and went on to become a major antagonist in the Harry Potter books and movies, but Helena Bonham Carter’s performance as Bellatrix made the character better and more popular. Bellatrix was sadistic and enjoyed torturing others, no matter if they were old or young, and she had a dangerous temper. Bonham Carter added a lot of unpredictability to the character, and it was the result of some brilliant improvisation on her part.

Bellatrix Lestrange smiling in Harry Potter

The Harry Potter reunion special is divided into four chapters, each covering two movies in the saga, and in chapter three Helena Bonham Carter joins the fun. While discussing the character of Bellatrix and the presence of Bonham Carter on the set, Tom Felton and Jason Isaacs shared that Bonham Carter improvised a lot of her scenes, which made the character a lot better. Felton shared that they never knew what she was going to come up with and that it was “very exciting for an actor” as “whatever she did on that take, it doesn’t mean she’s going to do the same on the next”. Isaacs even tried to be in charge of the scenes he shared with Bonham Carter in Harry Potter and the Order of the Phoenix, but she was “having the best time” and “was allowed to do anything she wanted”, and he tried and failed to keep her on toes. Bonham Carter’s improv made Bellatrix unpredictable not only to the audience but her co-stars too, adding to the insanity of the character and ultimately making her better.

Of course, Helena Bonham Carter’s performance as Bellatrix Lestrange in the Harry Potter movie saga was praised by critics and fans, and knowing that many of her scenes were improvised only make movie-Bellatrix an even better character (and proves why she’s one of the greatest of the saga) while also further establishing Helena Bonham Carter as one of the best actors of her generation.

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