Harry Potter series cast: See who's heading to Hogwarts for HBO's upcoming TV adaptation

John Lithgow as Albus Dumbledore

John Lithgow elicits respect, fear, and laughter in equal measure, having scored Emmys for three very different roles — as Winston Churchill on The Crown (2016–2019), the Trinity Killer on Dexter (2009), and Dick Solomon on sitcom 3rd Rock From the Sun (1996–2001). He's also a two-time Oscar nominee for turns in The World According to Garp (1982) and Terms of Endearment (1983).

Lithgow remains a compelling figure on film and TV, having recently appeared in Oscar-nominated movies like Killers of the Flower Moon (2023) and Conclave (2024), as well as FX's The Old Man (2022–2024).

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Lithgow plays Albus Dumbledore, the wise Hogwarts headmaster and founder of the Order of the Phoenix. Richard Harris originally portrayed Dumbledore in the first two Harry Potter films. After his death in 2002, Michael Gambon stepped into the role. Jude Law later played a younger version of the character in the Fantastic Beasts franchise.

Lithgow opened up about the role on a recent episode of the Smartless podcast. "You know, Dumbledore, he's kind of this nuclear weapon," Lithgow said. "He only goes off very, very occasionally. And I don't think it's gonna be that hard a job."

The 79-year-old Lithgow went on to say that playing Dumbledore across seven or eight years is "a wonderful way to grow old as an actor," adding, "I mean, the alternative is to just be hauled out once a year to play an Alzheimer's patient [with] an awful lot of weeping middle-aged children, you know."

Paapa Essiedu as Severus Snape

British actor Paapa Essiedu cut his teeth with the Royal Shakespeare Company and found success on the small screen opposite Michaela Coel on the BBC's I May Destroy You (2020).

He received Emmy and British Academy Television Award nominations for his performance, and went on to appear in series like Gangs of London (2020–2022), Black Mirror (2023), and Black Doves (2024) as well as the films Men (2022) and The Outrun (2024).

Essiedu will play Severus Snape, the Slytherin anti-hero famously played by the late Alan Rickman. In a note to Rickman, Rowling called Snape "my most complex character."

It will be interesting to see how Essiedu's Snape manifests in this telling, as the actor will come into the role knowing his full arc.

Rickman, who was given a key piece of information about the character by Rowling before the rest of the cast, often spoke about how that helped shape his performance, telling the Los Angeles Times in 2011, "I was always aware of my place in the story even as others around me were not.”

Janet McTeer as Minerva McGonagall

Janet McTeer is the recipient of a Golden Globe, a Tony, and an Olivier Award, as well as two Oscar nominations for her work in Tumbleweeds (1999) and Albert Nobbs (2011). Her other notable credits include the films Velvet Goldmine (1998), Maleficent (2014), and The Menu (2022), as well as series like Jessica Jones (2018) and Ozark (2018–2020).

This year, you can see her on the Paramount+ series MobLand and sprinting alongside Tom Cruise in the upcoming Mission: Impossible — The Final Reckoning.

McTeer plays Minerva McGonagall, Hogwarts professor and head of Gryffindor House. The character is as loyal as she is strict, serving as a mentor while instilling a healthy fear in her students.

Maggie Smith portrayed the character in the film franchise, while Fiona Glascott played a young Minerva in the Fantastic Beasts films.

Nick Frost as Rubeus Hagrid

Nick Frost came up alongside his pal Simon Pegg on the comedy series Spaced (1999–2001) before appearing in films like Shaun of the Dead (2004), Hot Fuzz (2007), and The World's End (2013). He recently voiced droid SM-33 on the Star Wars series Skeleton Crew (2024–present), and will next appear in Disney's live-action remake of How to Train Your Dragon.

The half-giant Hagrid is among the first characters we meet in the Harry Potter universe. A Hogwarts groundskeeper with a flowing brown beard, Hagrid was previously played by Robbie Coltrane, who died in 2022.

Luke Thallon as Quirinus Quirrell

Luke Thallon is a relative newcomer to the screen, with only a couple of small credits to his name. That said, he received rave reviews for his turn as Hamlet in the Royal Shakespeare Company's 2025 production.

He'll play Defence Against the Dark Arts professor Quirinus Quirrell, a key role in Harry Potter and the Sorcerer's Stone. The role was portrayed by Ian Hart in the film franchise.

Paul Whitehouse as Argus Filch

BAFTA-winning performer Paul Whitehouse was a star and co-creator of the BBC comedy series The Fast Show (1994–1997), as well as a collaborator with popular comedian Harry Enfield. He's also appeared in several popular films, including Corpse Bride (2005), Alice in Wonderland (2010), and The Death of Stalin (2017).

Interestingly, Whitehouse previously played a role in the Harry Potter film franchise, having shot material for Harry Potter and the Prisoner of Azkaban that didn't make the final cut. He played Sir Cadogan, a knight who appears in a painting in Hogwarts' Divination corridor.

In the Harry Potter TV series, Whitehouse will play Argus Filch, the feline-loving caretaker of Hogwarts. David Bradley played the role originally.