Happy holidays, everyone. It's Mary. Over the next few days, we're going to be rebroadcasting episodes

that stuck with us this year. And we'll check back in with a few of our guests and see how their sagas ended.

We wanted to start by considering the biggest story of the year, the pandemic, which reshaped the way

most of us live and caused so many people to die.

The very first interview we did about COVID,

it was at the beginning of March, one of the last conversations I had with anyone in person.

At the time, we knew a little bit about the coronavirus,

but not how it would upend our world.

But Peter Dashak, this episode's guest, he did.

Yeah, when did you first hear about what was happening in Wuhan with this outbreak?

Oh, I know exactly when it was New Year's Eve. It was during the day.

This is Peter Daschak.

He's a zoologist.

Lives in New York, works in China.

We were following rumors on the internet in China about this outbreak.

And I got these translated internet sites that were saying, not only is it a new virus, it's a coronavirus.

So I think people knew back then.

Coronavirus is one of Peter's areas of expertise.

He's been studying how infections, like this new one, COVID-19, move.

They start out in an animal, like, say, a bat.

Then they jump the way this one did.

You know, the minute we got the sequence that was released,

...