HBO has announced the first cast members for the upcoming "Harry Potter" TV series, including John Lithgow as Albus Dumbledore, Janet McTeer as Minerva McGonagall, Paapa Essiedu as Severus Snape, and Nick Frost as Rubeus Hagrid. Luke Thallon and Paul Whitehouse have also joined the cast in recurring roles. The series is described as a faithful adaptation of J.K. Rowling's book series and is set to begin filming this summer. Showrunners Francesca Gardiner and Mark Mylod expressed excitement about the talented cast bringing beloved characters to life.