Conversation so far:
Was Lord Voldemort in the film Harry Potter and the Half-Blood Prince?
Lord Voldemort does not appear in Harry Potter and the Half-Blood Prince.
How was Lord Voldemort's presence felt in Harry Potter and the Half-Blood Prince?
Lord Voldemort presence and actions are felt when he once again declares war, and begins to rise to power once more.

Question: What happens as he gains power?
Self-contained rewrite: What happens as Lord Voldemort gains power in Harry Potter and the Half-Blood Prince?