Chances are pretty good that if you eat fish you probably don’t think much about where it came from or how it got onto your plate. Fish sits under glass at the grocery store, or resides in plastic bags in freezers or, in some cases, in cans. Like beef, fish seem to go on forever, endlessly regenerating for your next meal. Nothing could be further from the truth.

The End of the Line is a documentary about fish that answers all the questions you never asked, from where the great fisheries of the world are, to the techniques used to make the catch. I think you will find after just a few minutes of watching that you are totally unprepared for the knowledge being laid on you. I know I was. The End of the Line has forever changed the way I look at fish. Unless you are dedicated to not seeing the truth when it’s placed before you, raw and uncompromised, you will have the same reaction.

The first bit of fact that’s presented, and one you wouldn’t think would have to be told to anyone, is that fish are not like cows. They are wild animals. All fish that are caught are living in the wilds of the oceans. Yes, there are such things as farmed fish, but I’ll deal with that in a little bit. Fully 99.99% of all fish are wild-caught and we depend on the natural function of the ecosystem to keep the oceans populated with fish so we can do this. The problem? We’re fishing too much, catching too much and destroying too much and the oceans are dying.

Let me say right now, before you claim this is a bunch of tree-hugging nonsense, that The End of the Line is not asking you to take anything it says at its word. The End of the Line is full of rigorous science and the science has spoken: if we continue to fish at the rates we are currently fishing, with the technologies we’re currently using, there will be no fishable waters by 2048. Period, full stop. That’s in my lifetime, folks, and probably yours, too. No more fish. No more tuna in a can. No more fish sticks. No more anything.

I saw a documentary fairly recently about how bluefin tuna have been fished to the brink of extinction. This is sad and can be averted, but it will take the willpower of millions to avoid eating the fish anymore and allowing their population to increase. What The End of the Line points out, however, and this is again borne out by empirical evidence, is that it’s possible to kill a species off not simply by catching them down to the last specimen, but by reducing their numbers to the point where they can no longer breed effectively. This is called a collapse and it has happened before. The movie opens with the collapse of the Canadian cod fishery. Despite efforts to stop the damage before it’s too late, nearly 20 years after the fishery was closed to all commercial fishing, the cod have not returned in numbers. They are going to be gone forever, or as close to forever as makes no difference.

This collapse pathway is happening in every fishery in every part of the world. Humans are so clever — and, sometimes, so oblivious to the harm we cause — that we’ve made ourselves the most efficient engine of species extinction as has ever existed. Hundreds of thousands of tons of fish are drawn from the seas every year. The oceans are not inexhaustible, and yet we continue on as if they are.

At one point there was reason to doubt this conclusion. Though fishermen were reporting reduced catches pretty much all over the world, the total global amount of catch continued to rise. How was this possible if the world was running out of fish? It turns out that the only country reporting year-upon-year increases in total catch was China and, as you may suspect already, China was being about as honest in those reports as they are about how much lead are in the toys they make. It was eventually revealed that the government officials in charge of tracking catches, in order to curry favor with other branches of government, had deliberately falsified their reports for years, perhaps even decades. Once the real numbers were out, we learned that China was no longer an exception. The depletion was on and it was on in a big way.

And it’s not just the sheer amount of the catches that causes a problem. The methods used are incredibly destructive. The huge nets that fishing trawlers use to make their catches also trap hundreds and even thousands of non-food varieties of fish, all of which die, thus decimating their overall numbers. Some of the nets drag upon the bottom of the ocean, ripping up all the habitat for the predator and prey species. One scientist likens it to plowing a field seven times a year. No wheat or corn or anything at all could grow under those conditions, so it should come as no surprise that the underwater ecosystem is likewise disrupted.

But what about aquaculture? Isn’t that a better way to do this? It turns out that farming a fish like salmon takes thousands of tons of wild-caught fish, ground up into meal for food pellets, just to produce a comparatively minuscule amount of product. It’s so inefficient that many aquaculture businesses are giving it up, the expense and difficulty far too high. Easier (and cheaper) to continue to plunder the seas.

You may wonder exactly what is to be done about all of this. Do we stop eating fish altogether? There’s no need for that. The End of the Line makes a case for sensible stewardship of our fisheries, governed by smart, effective treaties and enforcement, that can continue to provide food while also ensuring that we don’t send the oceans into global collapse. It’s not an easy solution by any means, but it is the only sane one.

I cannot recommend The End of the Line enough. As I said at the outset, this will change the way you look at a critical issue, one you may not even have realized was a problem. And the more people who know, the more likely something will be done about it before it’s too late.