10) Sirius Black
The Harry Potter movies have no end of memorable sequel characters, mainly the stream of new Defence Against the Dark Arts teachers like Kenneth Branagh’s Gilderoy Lockhart and Imelda Staunton as the despicable Professor Umbridge. For our money, though, the franchise’s strongest latter-day arrival comes from perhaps the series’ best film, The Prisoner of Azkaban.
Gary Oldman’s Sirius Black, Azkaban inmate cum Harry’s godfather, is one of the best of the series’ supporting cast – which is no mean feat when you consider that he turned up three films (or books) in. Though he is routinely underused in the movies (Oldman only appears as a CGI face in the fire in the whole of Goblet of Fire), the actor fleshes Black out into a likeable rogue, despite the lack of screentime. Due to this, his subsequent death in The Order of the Phoenix is one of the series’ defining emotional moments.