18. 'Harry Potter and the Prisoner of Azkaban' (2004)
The best Harry Potter movie happens to be the one with the most time travel. Coincidence? Hermione has been granted special permission to use a Time Turner because she wants more hours in the day to take a heavier courseload. But the climax of the story is Hermione and Harry's mission back in time a few hours to save Sirius Black and a hippogriff — revising what we've seen before like a crack film editor splicing in new material with Final Cut Pro.