Harry Potter: 12 Best Supporting Characters

One of the few characters across the series to actually pick up an expanded role in the films, Lord Voldemort's right-hand woman remains one of JK Rowling's most genuinely disturbed creations; a frenzied, swivel-eyed creation of pure, quasi-narcissistic malice who serves as an effective surrogate enemy for Harry below Tom Riddle himself.

Namechecked in Goblet of Fire before being introduced in Order of the Phoenix, Bellatrix's role is still vital, if relatively minimal in the books, with her murder of her cousin and Harry's godfather Sirius Black her key contribution on the page, until the latter half of Deathly Hallows.

In the films however, buoyed further by Helena Bonham-Carter's full-screech psychopathic turn, she leaves an even greater lasting impression with her expanded role in Half-Blood Prince, when she instigates an attack on the Weasleys' homestead of The Burrow. It's an often chilling characterisation - and one of the most memorable across the latter half of the series.