Harry Potter and the Cursed Child will tell the "untold part" of the boy wizard's story, Rowling has said.

Klaus' arrival sets events in motion for the sacrifice ritual -- which requires the demise of vampire, a witch, a werewolf, and of course, Elena -- on the night of the full moon.

Harry Potter and the Cursed Child will tell the "untold part" of the boy wizard's story, including the story of the lives of his murdered parents, Rowling has said.