But Jane Birkin may be best known for the highly-desirable Hermès fashion accessory that bears her name.

When I went to America, I don't in what interview, they said, "You mean Birkin, like the bag?"

So, I said, "Well, now the bag is going to sing."

And I thought, "On my obituary, it'll say, like, 'the bag' or something."

It is so funny that, after all this, you might be known for a bag.

I might; well, (it) could be worse.

Birkin first gained notice...

You weren't expecting us, were you?

... in Michelangelo Antonioni's 60's classic, "Blow-Up", when she romped, naked, across the screen.

She was just 18 and already married to John Barry,

the arranger of the James Bond theme.

But, then, he left her.

It was a disaster, and I was left with my daughter Kate.

And, so, I thought that I hadn't been capable of holding on to the man I loved.

Yeah.

And that, at 19, 20 years old, is terrible; I had no confidence in myself.

She went to Paris to audition for a film called "Slogan", and was paired with Serge Gainsbourg.

- From what I gather, it was not love at first sight. - No.

Suddenly I come trundling along, can't speak French, called him [French].

It's 'cause I didn't know any other French⏤

- You called him that to his face? - Yes!

But she got the part, and the man who was building a reputation as the French Bob Dylan.

He'd just come out of a very unhappy affair with Brigitte Bardot.

That's got to be slightly intimidating.

- No. - No?

I⏤No, I thought, "Gosh, if he'd been in love with the most beautiful woman in the world, which was Bardot at the time."

Yeah.

"And if he could take a look at me; to the contrary."

Gainsbourg had written a song for Bardot that he now wanted Birkin to sing.

The moaning may seem tame today, but, in 1969, it was incendiary.

- What did you make of the controversy over "Je t'aime"? - Oh, nothing.

It was great.

She recalls the reaction the first time she heard it played in a Paris restaurant.

We saw all their knives and forks in the air, like that.

Serge said, "I think we've got a hit record."

- Then the Pope goes and bans it, and the BBC. - Yeah, yeah.

It was in the bag.

- Best publicity you could get. - Can't get better.

For 13 years, Birkin and Gainsbourg were an inseparable it couple.

Songwriter and muse.

Until his drinking problem fractured the fairy tale.

So, suddenly, a beautiful boy comes along and, what's more, found me interesting.

- Whereas it was always "for Serge, for Serge"; he was the great man. - Yeah.

- I suppose I wanted to be noticed. - Did you feel⏤

That boy was French director Jacques Doillon, who asked her to play a depressed wife in his film, "The Prodigal Daughter".

No one had ever asked me to psychologically take over a part like that and to have a shirt buttoned up to here; the rest didn't interest him.

And then... Voila.

She moved in with Doillon, and they had a daughter, but Serge stayed in the picture, still writing songs for her until his death in 1991.

When Serge died, everything else collapsed and nothing was really the same again.

Birkin and Doillon split, and she focused on her three daughters.

Kate, her oldest, a successful photographer battled depression; in 2013, Kate Barry fell from her apartment window, an apparent suicide.

For nearly three years, Jane Birkin could barely leave her Paris home.

You feel as if someone's pulled the carpet from under your feet.

- Yeah. - You didn't see it coming.

I saw it coming on many other occasions, and I've been able to be there and to... I don't know.

But this time not, so... it took my confidence away completely.

Is your confidence coming back?

No, the confidence is one tiny thing.

She is irreplaceable.

And, uh... and the lack of her will be forever.

You have two other lovely successful daughters,

- who you must be very proud of. Yeah. - Very.

Charlotte has a record coming out right now, and a film.

Charlotte Gainsbourg is a renowned actress and singer.

And Lou Doillon has won the French Grammy.

At 71, Jane Birkin has begun to find her way again,

touring the world, performing Serge Gainsbourg's songs with an orchestra.

Next month, for the first time, she'll play Carnegie Hall in New York.

That's a pretty big name.

It's a big name, but it's just a big hall; you just have to fill it.

That's true, isn't it?

What's it meant for you to sing these songs this way now?

It's like being on the most wonderful velvet cushion.

It's like having lived with Cole Porter, and him writing songs for you from when I was 20 until his dying day.

So, he's given me a good turn in that he... he showed me a way.

A... a way to go on.