4. 'X-Men: Apocalypse'
X-Men: Apocalypse is the ninth film to feature the mutant superheroes in the past 16 years. Seeing this one without any knowledge of the previous ones would be like wandering into a Federico Fellini movie nine-tenths of the way through and trying to understand the plot. It would seem like complete gibberish. By this point in the X-Men universe, there's been a lot of time travel and many of the characters have younger doubles. It's very, very complicated. It still made $543.5 million, but that's much less than X-Men: Days of Future Past did just two years earlier.