There was a time when Hogwarts was thought of as a safe haven, but thanks to Lord Voldemort’s (Ralph Fiennes) tightening grip on the wizarding world, that isn’t the case anymore. Suspecting that the school may harbor an outright threat, Harry (Daniel Radcliffe) investigates Voldemort’s history while Dumbledore (Michael Gambon) attempts to prepare him for the monumental battle looming ever closer. In order to discover the key to Voldemort’s defenses, Dumbledore enlists the aid of the resourceful Professor Horace Slughorn (Jim Broadbent, Paddington 2, The Lady in the Van), who may have a clue as to their enemy’s weakness.