Rob Stewart encountered his first shark when he was just nine years old. The Toronto native says the shark was scared of him, meaning he didn’t have to be scared of it. And so, a love for the creatures—and all others—grew fierce.

In 2007, Stewart made a documentary called Sharkwater, about the exploitation and corruption surrounding the world’s shark populations. Since then, his plea to species in danger has widened to, coral reefs, the entire ocean, and, well, humanity itself. He spent four years travelling the world, meeting with other likeminded activists and discovering just how much danger the planet is in. The result is Revolution.

It’s a beautiful and startling documentary that features some amazing shots of the earth’s many unique creatures (how did I not know what a cuttlefish looked like until now?!). The underwater images that Stewart captured are breathtaking, highlighting just how diverse the life that lives under the sea is.

Throughout his travels, Stewart met with very dedicated people, from conservationists, to professors, to young children (the clip of a crying boy repeating, “It’s my future,” will stay with me for days). While individual circumstances and causes are different, all are unified with one single belief: The planet is in danger—and therefore we are in danger—and so we must act.

Revolution is informative, interesting, and worth a watch. It’ll make you think and rethink. It opens everywhere April 12.