The actor is the latest star to team up with the British-based activist collective as the narrator of short film Climate Crisis, and Why We Should Panic.
The video serves as an explainer regarding the current climate crisis, explaining what’s causing climate change, why governments must “enter crisis mode before it’s too late” and what will happen if they don’t.
“We’re living through a crucial moment in the history of our planet,” Knightley says in the video. “Yet we seem to charge ahead towards a catastrophic future rather than seizing the opportunity to pause and change out ways.
“Our children will grow up in this devastated world. What will we say when they ask, ‘The science and data were all there for everyone to see, why didn’t you stop this while you still could?’”
Climate Crisis, and Why We Should Panic is written, directed and animated by Miritte Ben Yitzchak and follows on from Extinction Emergency, and Why We Must Act Now, which was voiced by Naomie Harris and scored by Brian Eno.
Other stars, including Whoopi Goldberg, have also narrated videos for Extinction Rebellion.
Knightley is a supporter of a number of humanitarian causes and is the face of an Amnesty International campaign to support human rights.
Speaking about the project, the British actor said: “Lending my voice to the most urgent issue of our time felt like the right way for me to take a stand in the hope that we can leave a world worth living in for our children.
“Climate change and the ecological crisis are 2 sides of the same problem. This animation explains the climate change aspect in a no-nonsense way - though the message is horrifying to hear.”
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