Here's everything to know about HBO's 'Harry Potter' series, which may have recently cast its new Dumbledore After seven books, eight movies, one play and a whole spin-off series, Harry Potter is debuting on the small screen for the first time.

It seems John Lithgow spilled the (Bertie Bott's Every Flavor) beans about his involvement in HBO's in-the-works 'Harry Potter' series. 'A total surprise to me,' he says.

John Lithgow attends The Old Man" Season 1 NYC Tastemaker Event at ... [+] MOMA on June 14, 2022 in New York City. (Photo by Jamie McCarthy/) The first confirmed actor in the upcoming Harry Potter live-action TV series is John Lithgow who will be playing Hogwarts headmaster and wizard legend,