HBO's Harry Potter Series Casts Its Ghosts: Threlfall to Voice Sorting Hat

HBO has set David Threlfall as the voice of the Sorting Hat in its upcoming "Harry Potter" series, which debuts on HBO and HBO Max on December 25. The announcement fills out the spectral and portrait cast of Season 1, based on "Harry Potter and the Philosopher's Stone."

Leo Bill ("The Living and the Dead," "Alice in Wonderland") will play Nearly Headless Nick, the Gryffindor House ghost. Andrew Brooke ("PhoneShop," "The Agency") takes on The Bloody Baron, ghost of Slytherin. Daniel Fearn ("Things You Should Have Done," "Slow Horses") will play The Fat Friar, the Hufflepuff ghost. Laura Smyth ("Baby Reindeer") rounds out the group as The Fat Lady, the portrait guarding the entrance to Gryffindor House.

Notably absent from the announcement: a Ravenclaw house ghost. The Grey Lady, Ravenclaw's specter in the books, has no named actor yet.

Who is already in the cast?

Season 1 carries an expansive ensemble, led by three newcomers:

• Dominic McLaughlin as Harry Potter
• Arabella Stanton as Hermione Granger
• Alastair Stout as Ron Weasley

Around them sit established names:

• John Lithgow as Albus Dumbledore
• Janet McTeer as Minerva McGonagall
• Paapa Essiedu as Severus Snape
• Nick Frost as Rubeus Hagrid
• Johnny Flynn as Lucius Malfoy
• Bertie Carvel as Cornelius Fudge
• Luke Thallon as Quirinus Quirrell
• Katherine Parkinson as Molly Weasley
• Warwick Davis as Filius Flitwick
• Anton Lesser as Garrick Ollivander

Further casting includes Rory Wilmot as Neville Longbottom, Lox Pratt as Draco Malfoy, Leo Earley as Seamus Finnigan, Elijah Oshin as Dean Thomas, Tristan Harland as Fred Weasley, Gabriel Harland as George Weasley, Ruari Spooner as Percy Weasley, Alessia Leoni as Parvati Patil, Sienna Moosah as Lavender Brown, Finn Stephens as Vincent Crabbe, William Nash as Gregory Goyle, Sirine Saba as Pomona Sprout, Daniel Rigby as Vernon Dursley, Bel Powley as Petunia Dursley, Paul Whitehouse as Argus Filch, Amos Kitson as Dudley Dursley, Gracie Cochrane as Ginny Weasley, Richard Durden as Cuthbert Binns, Louise Brealey as Rolanda Hooch, Bríd Brennan as Poppy Pomfrey, Leigh Gill as Griphook, Harry Gilby as Charlie Weasley, Jasper Talbot as James Potter, and Hannah Chinn as Lily Potter.

The five new hires come with agency representation in place: Bill and Smyth with United Agents, Brooke with United Agents, Fearn with GDA Management, and Threlfall with Independent Talent.

What about Season 2?

Work on Season 2, adapted from "Harry Potter and the Chamber of Secrets," is already underway. Announced additions include:

• Kit Harington as Gilderoy Lockhart
• Bonnie Hill as Ginny Weasley
• Lenny Rush as Dobby
• Billy Barratt as Tom Riddle
• Rafe Spall as Arthur Weasley
• Molly Hewitt-Richards as Moaning Myrtle
• Jasper Ambrose as Colin Creevey

One detail stands out: Gracie Cochrane plays Ginny Weasley in Season 1, while Bonnie Hill takes the role in Season 2. HBO has offered no explanation for the recasting.

Francesca Gardiner writes and executive produces Season 1. Mark Mylod executive produces and directs multiple episodes for HBO, in association with Brontë Film and TV and Warner Bros. Television. Executive producers also include author J.K. Rowling, Neil Blair and Ruth Kenley-Letts of Brontë Film and TV, David Heyman of Heyday Films, Laura Neal, and Jon Brown.

What does this change for viewers? The ghost casting signals HBO is building the full Hogwarts apparatus, not a stripped-down retelling — and with Season 2 casting already public months before Season 1 airs, the network is treating this as a multi-year commitment.