“When we were kids, during the war, the world was full of fear. It could have ended any second. Everything was uncertain.” “What’s the difference?”

That’s Ginger, 16 years of age, nailing the terror of existence as a teenager during the Cuban Missile Crisis. The scary part now? She’s played by Elle Fanning, who’s only 14. How on earth are Ginger and Rosa’s young lead stars so ridiculously talented? What’s it like for writer-director Sally Potter to put her own formative experiences on the screen? And why would any man in any movie choose to leave Christina Hendricks?

The answer: Alice Englert. But what else did I find out as I hung around the Ginger and Rosa premiere at the London Film Festival, shouting random questions at passers by? Here are five things I learned from Ginger and Rosa’s premiere.

1. Elle Fanning rocks a cardigan even better than Tom Hardy

If we all looked this cool while wearing cardigans, the world would be a much fluffier place. Now will someone PLEASE make a film in which Tom Hardy and Elle Fanning wear cardigans together?

2. Sally Potter loves working with actors

Putting your own formative experiences on screen can’t be easy – “I put a bit of myself into all the characters”, Sally Potter told me – but what’s the most satisfying part of the job for the British director? It turns out it’s working with actors.

“I love working with actors, first and foremost. Performers are essential to everything I do. They’re what you see on screen. And a dancing background gives you a feeling for their movement, how characters move through the screen – and also camera movements, a sense of composition and space.”

3. Timothy Spall is a better man than me

Kids these days are getting younger and younger – and they’re getting better at doing stuff even younger than that. With people less than half his age turning in such brilliant performances, does Timothy Spall secretly resent them like me?

“Not at all - it’s a wonderful thing to see these youngsters being so good! Now… if it were somebody my age being brilliant and had a better part than me, I might!”

And that’s why he’s a far better man than me. That and the fact that he’s still so down to earth.

4. The word “arse-twitteringly”

Thanks to Mr. Spall, I now have a new favourite word. “Arse-twitteringly”.

”It’s hard for you in your 20s or 30s to understand that everybody in their 50s or 40s lived with a terrible constant paranoia… When something went wrong on the news, everyone was “We’re all going to go, we’re all going to go”. With the Berlin wall so close, we all knew it was a fascinating, arse-twitteringly paranoic state about the world. That stopped for about 35 minutes I think, internationally, and then it was replaced by the fear of terrorism. We’ve all got to be worried about something.

5. Elle Fanning is not a robot

First Super 8, now this. Elle Fanning is scarily good at acting. And, even scarier, she’s good at playing someone two years old than her. What’s her secret? Is she actually a robot? She said no.

“It’s funny. Sally and I never talked about age. It’s about the character now and how she’s dealing with that situation.”

So as a teenage girl, how different is she to Ginger?

”I think how me and Ginger relate is that she’s going through that period where she wants to be an adult and wants to make all those decisions, but she wants to be a kid and wants to be free still. She’s questioning things: what’s my view on religion and life and… stuff!”

6. Alice Englert wouldn’t leave Christina Hendricks for herself

It’s a hard plot point to believe at first – until you see Alice Englert’s performance, that is – but what was it like having a bloke leave Christina Hendricks for her? Alice exploded.

“OH GOD! When I found out that casting I thought “Problem! Problem! She wouldn’t do it! Why would anyone do that?!”

She fell in love with Rosa too, though.

“Rosa was always it for me – I always wanted to play her. I was sort of shivering, she terrified me and had seduced me, in a way. She was everything that you fantasise about doing, but never do it. And then she experiences the consequences of that. I actually totally respect her for what she does because she believes what’s she’s doing is right.”

Sally Potter’s emotionally-charged coming-of-age story is out in UK cinemas on Friday. It’s definitely worth seeing. Here’s our Ginger and Rosa review.