HBO has confirmed three new cast additions for Season 2 of its Harry Potter television series, based on J.K. Rowling's Chamber of Secrets. Billy Barratt will play the teenage Tom Riddle, Lenny Rush will take on the house-elf Dobby, and Bonnie Hill has been cast as Ginny Weasley following the departure of Season 1 actress Gracie Cochrane. The casting matters because it signals HBO's continued approach of casting younger actors than the original films used, and confirms the show is moving into its second book with production due to begin filming this autumn.

Barratt, a former International Emmy winner, is in his high teens, closer to the book's stated age of 16 for Riddle than the film adaptation's 23-year-old Christian Coulson. Rush, 17, takes on Dobby, a role that was CGI-animated in the films, with HBO yet to confirm whether the series will use CGI, motion capture or prosthetics. Hill replaces Cochrane, who announced in May she would not return, and will feature as Ginny becomes entangled with Riddle's diary. The trio join previously announced addition Kit Harington as Gilderoy Lockhart, alongside returning stars Dominic McLaughlin, Alastair Stout and Arabella Stanton, with Season 1 due to premiere on HBO and HBO Max at Christmas.