Los Angeles, Dec 21 (IANS): HBO Max has released the much-anticipated preview of "Harry Potter 20th Anniversary: Return to Hogwarts", its upcoming special that will reunite the actors and filmmakers from the eight-movie series, which will stream on January 1.

The only person missing from the reunion will be J.K. Rowling, the author of the books on which the films were based. Rowling has been under attack for remarks she had made about the trans community a year ago after retweeting an op-ed article on "people who menstruate".

The multi-millionaire author now claims to be a victim of the 'cancel culture' and calls herself a TERF -- or "trans exclusionary radical feminist".

"Harry Potter and the Sorcerer's Stone", which kicked off the film arm of the Wizarding World, was released in November 2001 -- and the special will commemorate the franchise's 20th anniversary, reports 'Variety'.

"Harry Potter 20th Anniversary: Return to Hogwarts", which will reunite actors Daniel Radcliffe, Rupert Grint and Emma Watson, was taped at the Warner Bros. Studio Tour London.

It will feature other talent from the movies, including Helena Bonham Carter, Robbie Coltrane, Ralph Fiennes, Jason Isaacs, Gary Oldman, Tom Felton, James Phelps, Oliver Phelps, Mark Williams, Bonnie Wright, Alfred Enoch, Matthew Lewis and Evanna Lynch. Filmmakers David Heyman, Chris Columbus, Alfonso Cuarón, Mike Newell and David Yates will also make appearances.

The trailer, according to 'Variety', features the cast reminiscing about the movies, as well as festivities in the Great Hall.

Watson says, "It feels like no time has passed -- and loads of time has passed." Radcliffe says that something that had scared him was "the implication that the most meaningful thing in our life was done", and that seeing everyone is "joyous", he realises "it wasn't though".