We'd already seen how Amy Tan's mother managed to escape an abusive marriage in China and build a new life for herself in the United States.

Now we turn to the man who helped make that life possible, Amy's father, John Tan.

John immigrated to America roughly two years before his wife, and ended up becoming a minister.

But he'd had an entirely different career back in China.

Records show he attended a university in Beijing where he was a talented engineering student, and that he even invented a radio transmitter that was sold commercially.

Wow.

Have you ever seen that before?

No, mm-mmm, no.

I wish I had known more about his accomplishments, you know, early on.

Because there was a separation between the past and the life that we knew with him, we didn't have access to that because he immigrated.

You know, you start your life over once you've immigrated.

You leave all that behind, the honors, the university that you went to.

And any of these inventions, that's gone.

You're starting over again.

Mm-hmm.

And that's what we knew.

Blackboard has been erased.

Yep.

Happily, our researchers were able to fill in much of that empty blackboard, mapping John's life in China from Beijing to a university in the city of Guilin, and finally, to Shanghai, where, as Amy's mother battled for her divorce, John made the momentous decision to board a ship.

"Yueh Han Tan, 30, engineer.

Nationality, China.

Final destination, San Francisco, California, to join friend Frank Leiu."

That is a record of the moment your father arrived in the United States of America.

What's it like to see that?

I'm just, I'm there.

I'm imagining him, you know, on this boat getting off, new world, new opportunities, leaving a lot of chaos and trouble behind, leaving a woman he loved behind.

Did he talk about the journey ever?

No, he didn't.

John obtained his visa to visit America by passing a US government exam for a scholarship, but he didn't choose to study engineering.

Instead, he enrolled in a divinity school, much to the dismay of his family back in China.

Amy believes that he made the decision because he was guilt=ridden about his adulterous affair with Du Qin.

He must have done this because of my mother.

His family cut him off.

His favorite sister cut him off.

My mother wouldn't speak to them, and he chose her.

Mm-hmm.

Yeah.

So he had to change his whole life and the direction of his life.

Do you know much about your ancestors on your father's side of your family tree?

I know that he was born to a family of 12, or 12 living births, and that his father was very religious and that there was this, I don't know, sort of a humorous anecdote that they had so many kids, they had their own church.

So yeah, I received one letter from my grandfather.

It was in English.

It was very formal.

And that's...that's about it.