Kit Harington's casting marks his third role in a HBO series after Game of Thrones and the financial drama Industry

Kit Harington is joining the highly anticipated Harry Potter TV series as the wizarding world's celebrity-turned-Hogwarts instructor Gilderoy Lockhart, HBO has confirmed to the BBC.

X-Men star Nicholas Hoult was originally cast in the upcoming second series earlier this month but had to reportedly leave due to scheduling issues., external

Best known for playing Jon Snow for eight seasons in the award-winning series Game of Thrones, Harington also appears in the BBC and HBO financial drama Industry. The star previously voiced Lockhart in the audio version of Harry Potter.

"I'm a huge Potter fan. I've got to be honest, he's one of my favourite characters," Harington told Collider., external "So, to be offered to play him is a real dream. I've had a taste of him (in the audiobook) and felt my way around him. He's just a wonderful creation."

Harry Potter and the Philosopher's Stone is due to premiere on Christmas this year on HBO Max.

Season two will adapt the second book in the series by JK Rowling, The Chamber of Secrets, which chronicles Potter's second year at the magical school.

"Before we begin year two at Hogwarts, there has been a slight change due to schedule: Kit Harington will be stepping into the role of Gilderoy Lockhart," a post reads on the official Harry Potter Instagram account. , external

The new series adaptation of the best-selling books stars newcomer Dominic McLaughlin as the boy wizard, Alastair Stout as his best friend Ron Weasley and Arabella Stanton as the young witch Hermione Granger.

Oscar-nominated actor Jon Lithgow has been cast as Hogwarts headmaster Albus Dumbledore and Nick Frost will play gamekeeper Rubeus Hagrid.

The new series stars Alastair Stout as Ron Weasley, Dominic McLaughlin as Harry Potter and Arabella Stanton as Hermione Granger.

The show could reunite Harington, who has said he is a lifelong fan of the books, with director and producer Mark Mylod, who worked on Game of Thrones and is directing some Harry Potter episodes. Mylod is an executive producer on the new series along with author JK Rowling.

Lockhart was portrayed in the Warner Bros Harry Potter films by Kenneth Branagh, and is a key character in Rowling's second book in the hugely successful book series.

The vain wizard, who authored several books on his purported encounters with dark creatures, serves as Hogwarts' latest professor for the defence against the dark arts and fancies himself as a mentor to Harry in his second year.

Hoult had faced some backlash from fans for his decision to join the show. Some cast members have spoken about facing criticism for taking part from those who are opposed to Rowling's views on trans rights.

Representatives for Harington and Hoult did not immediately respond to requests for comment.

The HBO series is expected to take 10 years to complete, as producers plan multiple seasons covering each of Rowling's seven books, which the eight blockbuster films were originally based on.

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