Ex ‘Harry Potter’ Star Makes Huge Prediction for HBO’s New Series

The new Harry Potter era is just months away, but comparisons with the original movies are already inevitable.

HBO will bring the Wizarding World back to television on December 25, 2026, with Dominic McLaughlin taking over as Harry Potter. Arabella Stanton plays Hermione Granger, while Alastair Stout stars as Ron Weasley.

The eight-episode first season, officially titled Harry Potter and the Philosopher’s Stone, also stars John Lithgow as Albus Dumbledore, Janet McTeer as Minerva McGonagall, Paapa Essiedu as Severus Snape, and Nick Frost as Rubeus Hagrid.

HBO has already renewed the series for a second season, adapting Harry Potter and the Chamber of Secrets. Kit Harington will play Gilderoy Lockhart, while Lenny Rush has been cast as Dobby, and Billy Barratt will appear as Tom Riddle. Bonnie Hill will take over as Ginny Weasley.

That second season is currently in preproduction, although reports claim filming has been pushed back after issues with unfinished scripts. HBO has not publicly confirmed the reported production problems.

The bigger question, however, is whether a new adaptation can justify retelling a story already defined for millions of fans by Daniel Radcliffe, Rupert Grint, Emma Watson, and the rest of the original movie cast.

One former Harry Potter star thinks it can.

Gary Oldman Predicts a More Satisfying Harry Potter

Gary Oldman, who played Sirius Black in the original movies, believes HBO has an advantage that Warner Bros.’ film series simply did not have: time.

Speaking to Entertainment Weekly at the Toronto International Film Festival, Oldman reflected on the compromises required when adapting Rowling’s lengthy novels into theatrical releases.

“We had to cut a lot, and still we could only get the films down to, like, three hours,” he said.

Those cuts became increasingly significant as the books grew longer and more complicated. By the later movies, entire characters, relationships, histories, and subplots had been condensed or removed to keep the central story moving.

Oldman believes HBO’s longer format could change that.

“I believe [the TV series is] gonna do it pretty much word-for-word, which I think, as a viewer, would be more satisfying,” Oldman added.

He also acknowledged that “a lot of character detail was sacrificed” when the books were adapted for cinema.

HBO has repeatedly positioned the series as a faithful new adaptation of Rowling’s novels. The company has even confirmed that the first season will restore material never previously depicted onscreen.

That includes Harry’s experiences at his Muggle school before Hogwarts, material that was mentioned in the original novel but never appeared in the 2001 movie.

Sirius Black Shows What the Movies Had to Leave Out

Oldman’s own character provides a particularly clear example of what HBO could gain from having more screen time.

Sirius made his movie debut in Harry Potter and the Prisoner of Azkaban (2004), before returning in Harry Potter and the Goblet of Fire (2005), Order of the Phoenix (2007), and later installments.

His basic story survives intact, but the films dramatically simplify his personality and relationship with Harry.

In the books, Sirius becomes increasingly frustrated while confined to Grimmauld Place. His recklessness, anger, loneliness, and resentment become important parts of his characterization, particularly during Order of the Phoenix.

His bond with Harry is also less straightforward.

Sirius occasionally treats Harry as an extension of his late best friend, James Potter, and becomes disappointed when Harry refuses to behave as James might have. That tension adds another layer to what is otherwise presented as a largely paternal relationship in the movies.

The books also spend considerable time exploring Sirius’ relationship with the Black family, his rejection of their pure-blood beliefs, his decision to leave home, and the history of his younger brother, Regulus Black.

Other characters could benefit for the same reason.

Ron Weasley and Ginny Weasley both lost significant material in the transition from page to screen, while several of JK Rowling’s storylines were condensed or eliminated completely. Peeves, for example, never appeared in the finished movies but is being restored for HBO’s adaptation.

Oldman, meanwhile, remains complimentary about the original films and their legacy. His prediction is not that the movies failed, but that television gives the same story room to include material that cinema could not accommodate.

HBO has not yet announced who will succeed Oldman as Sirius Black. The character does not properly enter Harry’s story until Prisoner of Azkaban, meaning casting is likely still some way off.

Do you think HBO’s Harry Potter series will be better than the movies?