Considering the thousands of people who work on a film and the many more who are involved in distribution and marketing, it's incredibly difficult to keep spoilers, twists and revelations under wraps.
This is especially true in an age where everyone carries a camera in their pocket and internet access is only a few brief taps away, but even decades ago, information could still leak out via a talkative cast member, well-placed photographer or unnecessarily-detailed advance movie review.
It's not just the fact that the principle of leaking private information is wrong, either, it's the fact that most moviegoers will have a much more enjoyable time at the cinema if they know very little about a film's story.
Movie studios and filmmakers are aware of this, and some of the lengths they've gone to to keep plot details under lock-and-key are unbelievable to discover.
These range from alternate scenes being shot to flat-out lies being told to the general public, and though you're probably aware of the following plot moments by now, you may have one of these oddball methods to thank for your initial spoiler-free cinema experience.
8. Marvel Tricks The Press To Keep Yondu's Death A Surprise - Guardians Of The Galaxy Vol. 2
The Marvel Cinematic Universe contains some of the biggest films on the movie calendar, so by default, they're subject to high levels of scrutiny, and will be watched my millions and millions of people even with an underwhelming box-office run.
Guardians Of The Galaxy Vol. 2 was no different, and as a result, the filmmakers went to some extreme lengths to keep what was quite possibly the film's biggest plot point - the death of Michael Rooker's Yondu - a surprise.
Months before the sequel came out, filming on the upcoming Avengers: Infinity War had already begun. At that point, we knew the movie would feature the Guardians and we all assumed that would include Yondu too, but when things started leaking from the Infinity War set and more and more information started being revealed, the character was nowhere to be found.
And Yondu not appearing in Infinity War could mean only one thing; he dies in Vol. 2.
Many people (correctly) jumped to this conclusion, so in an attempt to keep his death a secret and throw fans off the scent, Rooker, Marvel and Guardians director James Gunn banded together and decided to "leak" pictures of Rooker on the Infinity War set.
Obviously, this was all a giant ruse. Yondu did die in Vol. 2 and will not be in Infinity War, and this picture-prank was eventually confirmed by Gunn on his official Twitter account.