HBO 'Harry Potter' Series Cast And Characters, Explained

Over 14 years after the original film series concluded, Harry Potter is returning to the screen with a brand-new adaptation from HBO. Rather than a film adaptation, HBO will produce the first live-action Harry Potter TV show adaptation. 

The casting process for HBO’s series was extensive, with over 32,000 children auditioning for the roles of the golden trio. Now, HBO’s Harry Potter has found its Harry, Ron, Hermione, and many of Hogwarts’ beloved professors. Viewers can use our guide to meet the new Harry Potter cast and find out where they’ve seen them before.

Dominic McLaughlin (Harry Potter)

Previously played by Daniel Radcliffe

Dominic McLaughlin has been cast in the titular role in HBO’s Harry Potter. As Potter, he will portray the iconic Boy Who Lived, an orphaned child who discovers he’s a wizard on his 11th birthday and goes off to train at Hogwarts School of Witchcraft and Wizardry. McLaughlin is a newcomer to the industry. He will make his film debut in the upcoming Sky original comedy Grow, sharing the screen with Golda Rosheuvel. He will also star in the BBC adaptation of Marilyn Kaye’s novel, Gifted. Before breaking into the industry, he attended Performance Academy Scotland and starred in Macbeth at the Royal Highland Centre.

Arabella Stanton (Hermione Granger)

Previously played by Emma Watson

Arabella Stanton has also joined the golden trio, starring in HBO’s Harry Potter as Hermione Granger, the intelligent, perfectionist Muggle-born wizard who becomes friends with Potter. Stanton is another newcomer to the industry, with her role as Hermione marking her first TV appearance. However, she previously appeared on stage as Matilda in the West End’s Matilda the Musical and as Control in the theatre’s production of Starlight Express. A clip of her monologue at the House of Talent acting school has convinced viewers she’s the perfect Hermione, as she nails the character's haughty mannerisms and know-it-all attitude.

Alastair Stout (Ron Weasley)

Previously played by Rupert Grint

Alastair Stout rounds out the golden trio with his role as Ron Weasley in Harry Potter. Ron is another young wizarding student and the mischievous and impulsive best friend of Harry and Hermione, known for his humor and bravery. Like McLaughlin and Stanton, Stout is a newcomer to Hollywood, with his role as Ron marking his first major acting role. Before his casting in HBO’s Harry Potter, Stout appeared in an advertisement for Albert Bartlett potatoes. In the “Roll on Jersey Royal Season” commercial, he portrays a son at dinnertime. 

John Lithgow (Albus Dumbledore)

Previously played by Richard Harris and Michael Gambon

John Lithgow, one of the most decorated actors to join the Harry Potter series, will take on the role of Albus Dumbledore. Dumbledore is the headmaster of Hogwarts and the founder of the Order of the Phoenix, an organization tasked with fighting Lord Voldemort. He is among the most powerful and wisest wizards in the Harry Potter series. Lithgow is an award-winning actor best known for his Oscar-nominated role as Roberta Muldoon in The World According to Garp, which he starred in alongside Robin Williams. More recently, he starred as Winston Churchill in The Crown and as Cardinal Joseph Tremblay in the critically acclaimed political thriller, Conclave.

Paapa Essiedu (Severus Snape)

Previously played by Alan Rickman

Paapa Essiedu will star in Harry Potter as Severus Snape. Snape is a professor at Hogwarts, having served as a Potions and Defense Against the Dark Arts teacher. While cold, calculated, and sometimes cruel, he’s a loyal friend to Dumbledore. Essiedu is relatively new to the film industry, boasting his breakthrough role in 2020 as Kwame in BBC’s critically-acclaimed black comedy, I May Destroy You. Following the success of I May Destroy You, he tapped the lead role of George, a man trapped in a time loop, in The Lazarus Project, and appeared in Season 6 of the anthology series Black Mirror.

Janet McTeer (Minerva McGonagall)

Previously played by Maggie Smith

Janet McTeer will appear in the Harry Potter series as Professor Minerva McGonagall. McGonagall is a professor at Hogwarts and the head of House Gryffindor. McGonagall is a stern, no-nonsense, seasoned professor at Hogwarts but also a very loyal friend of Dumbledore’s and a fierce protector of her students. McTeer is a highly decorated actor who earned an Oscar nomination and a Golden Globe for her performance as nomadic single mother Mary Jo Walker in Tumbleweeds. She also gained recognition for her role as Jacquetta of Luxembourg in The White Queen. Most recently, McTeer starred in Mission: Impossible – The Final Reckoning as Secretary of State Walters.

Nick Frost (Rubeus Hagrid)

Previously played by Robbie Coltrane

Nick Frost will take on the role of the lovable half-giant Rubeus Hagrid in the Harry Potter series. Hagrid is a groundskeeper at Hogwarts and a prominent member of the Order of the Phoenix. While he struggles with keeping secrets, he’s one of Hogwarts' kindest and most loyal figures. Frost is best known for starring in the zombie comedy Shaun of the Dead and the sci-fi comedy Paul. Most recently, he appeared in the live-action adaptation of How to Train Your Dragon as the blacksmith Gobber the Belch.

Luke Thallon (Quirinus Quirrell)

Previously played by Ian Hart

Luke Thallon has been tapped to star in the Harry Potter series as Quirinus Quirrell, Hogwarts’ Defense Against the Dark Arts Professor. Quirrell started his tenure at Hogwarts as a Muggle Studies Professor before his promotion to Defense Against the Dark Arts. However, he took a year-long sabbatical before changing positions and returned from his trip as a changed man. Thallon is a newcomer to the film industry, having made his film debut in Yorgos Lanthimos’ The Favourite. Before entering the TV and film industry, he appeared on stage, boasting roles in plays like Leopoldstadt and Hamlet.

Paul Whitehouse (Argus Filch)

Previously played by David Bradley

Rounding out the confirmed cast for the Harry Potter series so far is Paul Whitehouse, who will portray Argus Filch. Filch is the grumpy Hogwarts caretaker, who is a stickler for rules. Although he’s not one of the most prominent characters, he’s always lurking about Hogwarts with his cat, Mrs. Norris, looking for troublemakers. Whitehouse actually has ties to the original Harry Potter film series, as he appeared as a portrait of Sir Cadogan in Hogwarts in a deleted scene in Harry Potter and the Prisoner of Azkaban. He has also starred in the sketch comedies Harry & Paul and Harry Enfield and Chums.

Where To Watch The New 'Harry Potter' Cast's Shows And Movies Online

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