In the movie \'Harry Potter and The Half-Blood Prince\' Lord Voldemort is tightening his grip on both the Muggle\'s and the wizard\'s world, and Hogwarts is no longer a safe getaway. Harry has a feeling that there are dangers within the walls of the castle, but Dumbledore is more focused on preparing Harry for the next battle, which is very soon. Together they are trying to find out something to get through Voldemort\'s defence and get rid of him. Dumbledore hires his old friend and colleague Horace Slughorn, in which he believes to hold important information.