Once You Know
2021, French. Directed by Emmanuel Cappellin.
Today, like a ship entering the storm, the world faces climate change induced collapse. Once You Know, by director Emmanuel Cappellin, is a poetic and poignant exploration of how four of the world’s leading climate scientists and energy experts find truth, chaos, and hope in their work.
- Runtime
- 1h 45m
- Post-credits
- None listed
- Language
- French
- Rated
- Check local
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Where to watch Once You Know
Once You Know is streaming on Amazon Prime Video in India.
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YouTubeAvailability in India as of 10 November 2026. Streaming data by JustWatch.
Cast & crew
Details
- Released
- 22 September 2021
- Original title
- Une fois que tu sais
- Country
- Bangladesh, France, Greece, United States of America
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News & fan talk
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Once You Know: quick answers
Is Once You Know worth watching?
Once You Know doesn’t have enough ratings for a verdict yet.
How long is Once You Know?
Once You Know runs 105 minutes (1h 45m).
Does Once You Know have a post-credits scene?
None is listed for Once You Know. Viewers tag these on TMDB, so a brand-new film may not be tagged yet.
Once You Know parents guide: is it suitable for kids?
No age rating is listed for Once You Know yet.
Which OTT platform is Once You Know on?
Once You Know is streaming on Amazon Prime Video in India. (Checked 10 November 2026.)
What movies are like Once You Know?
If you liked Once You Know, try Come See Me in the Good Light, Earth: One Amazing Day, A Toxic Love Story.
Who directed Once You Know?
Once You Know (2021) was directed by Emmanuel Cappellin and stars Jean-Marc Jancovici, Pablo Servigne, Richard Heinberg.