In the 1980s, the world faced a huge problem: there was a rapidly expanding hole in the ozone layer. If it continued to grow, rates of skin cancer could skyrocket, photosynthesis would be impaired, agricultural production would plummet, and entire ecosystems would collapse. So, what happened? Stephanie Honchell Smith shares how decisive global cooperation helped restore the ozone layer. Lesson by Stephanie Honchell Smith, directed by Denys Spolitak.