Greta travels through North America on her way to a UN climate conference in Chile. To understand the impact of climate change, she stops at three key locations that reveal how the planet is changing. The Canadian Rockies, where temperature changes have changed the ecosystem, a glacier that is melting faster than models predict, and a town in California devastated by fires in 2018.

Greta sets off to the annual World Economic Forum in Davos, Switzerland. As she travels across Europe, Greta finds out what is preventing more rapid action to tackle global warming. She also meets with a figure who's been an inspiration to her, Sir David Attenborough.

As the world is bought to a standstill by Covid-19, Greta has to put her plans on hold. With mass protests off the agenda, Greta investigates what else could help limit the impact of climate change. Having recovered from Covid-19, Greta also explores what lessons can be learned from the international response to the pandemic.