We will change, we will change, we will change.

There is something about marching in a crowd,

no matter how big or small, when you're chanting the same chance,

and it sounds cheesy, but I'm gonna say it,

when you're marching to the same beat.

Soul South Korea, 2019.

And Eugene Kim is joining a crowd of teenagers,

marching against climate change and going on strike.

It was on a Friday afternoon and more than 300, 400 people showed up,

which is huge in Korea,

because it's really hard to get excused absences for students.

And I was not expecting that many people,

but the crowd was really big, I was really surprised.

In that year alone, more than a million students

joined the global protest movement,

skipping school and taking to the streets to make their voices heard.

While the strikes captured the public's attention,

they weren't forcing the kind of change the teenagers were demanding.

We were already quite frustrated from the lack of action that had followed,

almost a year of campaigning on the streets.

We held four massive school strikes for climate,

and we were raising awareness in the public,

...