FAIR WARNING: this is more a diatribe of my opinions than a review of the movie.
The kangaroo is the national icon of Australia, and of course unique to that country (okay, they have wallabies in New Zealand). It's an unusual creature, and a big tourist draw. It's also constantly being culled as a "pest" and sold as leather and either pet food locally or speciality meat overseas. The film gives more voice to those opposed to the killing of kangaroos than those in favour, but at least it does spend a bit of time with the opposition.
I admit to being fascinated by the word "pest." Squirrels are "pests" if you live in almost any North American city: they steal bird food, they chew phone lines, and they gnaw their way into your attic and build a nest. In the state of Georgia, deer are considered pests - and I came to that way of thinking when I lived there because there are so many of them that driving at night (this was a small town) was dangerous because they were always leaping across the road. Regardless of the dictionary definition, what we mean by the word "pest" is "something that interferes with my living the way I want to."
Australian farmers consider kangaroos pests because they eat greenery that the farmer's sheep could be eating - never mind that the sheep is the invasive species. One kangaroo fan (I think it was Terri Irwin) claimed kangaroos "eat different parts of the greenery," but of course nobody can prove that either way because it hasn't been studied.
What we get a lot of in the movie is 1) talking heads, 2) footage of the hunters, and of course 3) footage of kangaroos. They did manage to convince me of a few things: the hunters aren't well regulated, the meat is badly handled, and the government is fudging its figures. That last is unsurprising: show me a government that doesn't, on almost any subject. Part of the issue is the sheer scale a country-wide government deals in. But the other side of that coin is something the movie seemed surprised about: the government body meant to regulate the kangaroo industry has become an advocate for that industry. This doesn't surprise me: where does the money come from? The industry - taxation at the very least, likely huge donations. And trust me, the government aren't getting a lot of money from the conservationists on the other side of the argument. So of course the government bends the figures a bit to favour the industry that feeds it.
One thing they wanted us to know about was how brutal the killings could be, and they spend a bit of time on the killing of the joeys. A "joey" is an infant kangaroo still in its mother's pouch. When the hunters kill a mother, they pull the joey out of the pouch, grab them by the hind legs, and swing them against the truck or a rock to kill them. They had footage of that - it's not just something hunters do: it's government documented policy ... with some minor caveat that it should be done quickly and humanely.
On the flip-side of that, I snorted at the person who claimed "if Australians knew how inhumane the Kangaroo hunt is, they'd never eat Kangaroo again!" Really? Have you ever seen a commercial pig, chicken, or cattle farm? Kangaroos may die inhumanely, but pigs, chickens, and cattle are raised in the most confined space it's possible to keep them in: their entire life is pain and inhumanity. And we all eat that all the time, so I'm not buying your conclusion.
I'm okay with (if not enthusiastic about) hunting, if it's properly managed. But if kangaroos are endangered by the hunt, I'm in favour of a massive curtailing of the hunt. Although how successful that would be is somewhat dubious: one of the talking heads pointed out what a complete failure that's been for our oceans. But in the case of the kangaroo, the management would be contained inside one country, thus eliminating the ocean's biggest management problem. The problem is that the government and the kangaroo meat industry seem to be successfully obfuscating the numbers.
In the end, I found the movie clearly biased and lacking in hard facts (not entirely their fault). It was also a bit long.