20 Documentary Movies You Must See Before You Die

15. Blackfish (2013)

For years people went to SeaWorld (and countless other aquamarine parks) under the impression that the animals there were cared for and looked after.

Blackfish is the documentary that changed everything, exposing the horrors that take place behind the scenes of these "theme parks" of which so many people were plainly oblivious to - so much so, in fact, that the backlash resulting from Blackfish's release prompted SeaWorld to announce plans to phase out its world famous orca show.

As such, Blackfish - directed by Gabriela Cowperthwaite - is essential viewing, because it really is a piece of documentary that changed the world in a huge way. The footage here, most of which concerns the mistreatment of orcas in captivity and the associated ill-effects, brings new meaning to the term "eye opening." Indeed, thanks to this gripping and heartbreaking documentary, you are unlikely to ever visit a SeaWorld park again.