Gary Oldman, who played Sirius Black in the Harry Potter films, has said HBO's forthcoming television adaptation of the franchise could prove "more satisfying" than the original movies because it will follow the books far more closely. Speaking to Entertainment Weekly, he explained that the films had to compress the story dramatically, sacrificing character detail, whereas the series has room to adapt the source material almost word-for-word. His comments add a notable endorsement from within the original cast as anticipation builds ahead of the show's launch.

Oldman first joined the film series in 2004's Harry Potter and the Prisoner of Azkaban and went on to appear in three further instalments, his last being a cameo in 2011's Deathly Hallows – Part 2. He also praised original director Chris Columbus for shaping the franchise's world and casting, calling the films' success a "phenomenon" unlikely to be repeated. The HBO series, due to debut at Christmas 2026 on HBO Max, stars Dominic McLaughlin as Harry Potter alongside Arabella Stanton, Alastair Stout, John Lithgow, Janet McTeer and Nick Frost, among a large ensemble cast.