Some of the most fulfilling moments in my life as an actor are when I play roles that speak to the challenges facing humanity. In The Avengers, for example, in which I play the Hulk, the team tries to undo the “the snap” – an apocalyptic event brought about by the villain Thanos to eradicate half of all living beings. As a good friend of mine says: “Fantasy is not an escape from our world, but an invitation to go deeper into it.” The simple fact is that humanity has triggered extinction events – and the collapse of the Amazon is a disaster that will be terrible for all of us in real life. We are on the brink of what scientists are calling a “tipping point” for the Amazon basin, meaning that the destruction will get to a point where the forest can no longer regenerate. This is Earth’s endgame. Over 10,000 species could be wiped out, starting a domino effect that would affect our planet’s climate, our water, and food supplies everywhere – taking many human lives with it. So even if you live on the other side of the globe, this is very much your problem, too. Scientists tell us that we don’t have much time to reverse this – and to do so, we must protect 80% of the Amazon and sustainably manage the other 20%. The good news is that there are real-life Avengers showing us the way. Because while we have been playing at consuming and destroying, Indigenous peoples have been conserving almost all biodiversity this planet still holds. No joke: 80% of the planet’s remaining biodiversity is on Indigenous land. Silently, they have proven that the smartest way to save us all is to recognise and protect their territories. But tragically, these Indigenous peoples are being removed, attacked and even killed by multiple villains: hostile governments, powerful lobbies, trafficking, loggers and mining. And this coming week, they will face an important battle: the Amazon summit. Leaders from all Amazon countries will gather in Brazil to decide the future of the forest. And our Amazon saviours will be fighting to guarantee we get all the protections we need. It is time for reinforcements to arrive from all sides, and for all of us to realise and come to terms with how high the stakes are. Indigenous wisdom says that the decisions we make today should result in a sustainable world seven generations into the future. This is a calling from the children of the generations that will follow us. We are all being asked to assemble and awaken what is heroic in us. Let’s pledge together to help them. We need to turn all eyes to the Amazon summit as a decisive moment for the whole world. The best way to do this is by making leaders aware that we are all watching what they do. And that public gaze is already bearing fruit. In July, thanks to action by the new Brazilian government, deforestation fell by at least 60% compared to the same month last year. Now we need them to commit to recognising Indigenous territories and protecting 80% of the forest now, in line with scientific recommendations. I’ve heard it said that there used to be many “environmental issues”. But now, it’s all one struggle: for life itself. Such a struggle reminds me of Avengers: Endgame barrelling towards its conclusion and of the 14,000,605 timelines that Doctor Strange witnesses: of all of them, there was only one in which they won. The odds were stacked against them just as they appear to be against us. But as with the Avengers, only our actions together can beat the odds so that life on Earth wins. Let’s do this. Mark Ruffalo is an actor, producer, activist, and co-founder of The Solutions Project