Movies often make us suspend our disbelief to take us on magical or futuristic journeys, where unicorns are real and humans have already explored more than just our solar system. And while usually those unrealistic events are explained by in-universe laws, there are times when we sit up, squint at

http://www.youtube.com/watch?v=NDe_xAfD7WQ Ever wonder why Harry and Hermione can’t just go back in time several times over if they fuck up while trying to save Buckbeak in The Prisoner of Azkaban? Curious as to how The Avengers pulled out a seemingly random victory at the end of the movie? Do the