Voldemort actor Ralph Fiennes's nine-year-old nephew has been cast in the role of the young Voldemort in the sixth Harry Potter movie.
Hero Fiennes Tiffin will play the 11-year-old Tom Riddle. And Frank Dillane will play teenage Voldemort.
Earlier this month, Newsround exclusively revealed that Jessie Cave would play Lavender Brown and Helen McCrory would play Narcissa Malfoy.
Both pieces of casting have now been officially confirmed by Warner Bros.
The film company have also said that actor Jim Broadbent will play Potions Master Professor Slughorn.
Harry Potter and the Half-Blood Prince follows Harry's sixth year at Hogwarts school.
And the story shows him being prepared for the battle with Lord Voldemort that he knows must come.
The film will be released on 21 November 2008.