This is 99% invisible. I'm Roman Mars.

The Tokyo Rail and metro systems make up one of the largest rapid transit networks in the world.

More than 14 billion people walk through its turnstiles every year.

That's about 40 million rides every single day. On a typical morning during rush hour,

commuters stand cheek to jowl in crammed train carriages. The busy stations even employ people

pushers known as OSHA who make sure everyone is packed in before the doors close. But last year, at the start of the COVID epidemic,

after the Japanese government declared a state of emergency,

the trains emptied out.

That's Tokyo-based producer Daniel Simo.

Suddenly, there were no Ashia to be seen.

In fact, the trains were so empty in the mornings that if you had to take one,

there was no need to stand anymore.

For a few weeks at least, most people had stopped riding the train.

Most, but not all.

It was kind of strange because everybody was supposed to stay at home, but I had to go out every single day.

That's Miho Tanaka.

She's not a health professional or an essential worker.

She runs a company in Tokyo that helps foreign businesses

set up in Japan.

And yet, at the height of the pandemic,

she still found herself commuting on a daily basis,

and not just in the metro, and not just to one place.

...