 Daily Mail | Potter tribute to murdered actor BBC News Cast and crew from the new Harry Potter film are to wear white ribbons on their wrists at its world premiere as a mark of respect to murdered actor Rob Knox. Mr Knox, 18, who played Marcus Belby in the forthcoming Harry Potter and the Half-Blood Prince ... Romance rocks wizard world in new Potter movie Harry Potter's Emma Watson: my dream role as a university student Grint plays down his swine flu |