HBO Max sets 20th-anniversary Harry Potter retrospective special featuring the cast -- but not J.K. Rowling -- for New Year's Day

Harry Potter 20th Anniversary: Return to Hogwarts will feature filmmaker Chris Columbus joining cast members Daniel Radcliffe, Rupert Grint and Emma Watson, Helena Bonham Carter, Robbie Coltrane, Ralph Fiennes, Jason Isaacs, Gary Oldman, Imelda Staunton, Tom Felton, James Phelps, Oliver Phelps, Mark Williams, Bonnie Wright, Alfred Enoch, Matthew Lewis, Evanna Lynch and Ian Hart in the retrospective special. But as The Hollywood Reporter notes, "there’s one notable omission from the list of participants: creator J.K. Rowling."