RESCUED BY THE MAYOR

I’m just calming down after spending the past six months promoting The Age of Stupid, my film on climate change. It’s taken me seven years to make and it’s been a big project. I was walking home up a side street to my house in Camden, north London, on Monday night. It was about 9pm, and when I looked up there were three girls there. They must have been aged about 11 and they were mumbling vague threats. Well, I’ve lived in London all my life — I thought they were just talking among themselves. Then they surrounded me, and it was frightening. One had a metal bar about the length of a broom handle, even though she was practically a child.

Five seconds later I saw a cyclist come past, and thought: “Oh good, a large man.” Contrary to reports, I did not scream for help. I just said, quite normally: “Excuse me, can you help?” He stopped and turned around, and said: “Are you okay?” And I said: “It’s Boris!”

In a way, I wanted to share the moment with the girls because it was so surreal. But the minute I said: “It’s the mayor of London”, they fled, and he chased after them, calling them “oiks”. He was my knight on a shining bicycle. I’ve never had any trouble in London, and I’ve never met the mayor of London, so to have both at once was astounding.

Five minutes later he reappeared and walked me home. We talked about things such as bike lanes and the congestion charge. I didn’t vote for him — I supported Ken Livingstone. The day Boris got in, I was devastated. But if you are going to have someone save you from a mugging, Boris would be a pretty good choice. The next day he sent me a lovely tweet, saying he hoped I was okay.

PRESS GANG

I did a full interview with the police. I had said I couldn’t be bothered to make a statement, but they said girls aged 10 who went around threatening people with iron bars were going to grow up into extremely dangerous teenagers unless they were stopped. I thought that was a good point and I should help. They said they thought they had a good chance of catching them, as there were loads of CCTV cameras in the area.

I usually listen to music while I’m walking on my own in the middle of the night, as it’s the best way to solve tricky film structure problems. I may possibly stop that. Then again, I’ve been doing it for 30 years and never had any trouble, so I don’t think I will.

By about 4pm on Tuesday the story had got out. The press phoned me about 70 times, called my house, called my office, called members of my family, found out where I lived, posted interview requests through my door. Imagine if I had done something bad!

That night I was at the Grierson documentary awards. When I came home with Lizzie Gillett, my producer, I could see lots of cars waiting outside. They were full of photographers, so I walked past and slept on Lizzie’s sofa. That was the most frightening part of the episode. It was a real pain because I was in my smart suit, not at all what I would wear the next day.

BILLIONAIRE DINING

I had dinner at Quo Vadis in Soho with a billionaire. He was very charismatic. He’s in the list of the top 20 philanthropic billionaires, and no, I can’t tell you who he is. And no, he’s not a vegetarian. I’ve been a vegetarian since I was a kid. I used to be a vegan but I gave that up. It got so boring, basically, just eating nuts and vegetables.

NO MORE ROCK’N’ROLL

I’m handing over my environmental campaign to its new director. I’ve said everything I’m going to say. But to feel you have done your life’s work by the age of 37 is fulfilling. I was a drummer when I was young. I joined the group the Band of Holy Joy when I was 17. I was schoolgirl by day and rock’n’roller by night. Fantastic. But after three or four years I started thinking I could do something more productive with my life than just hitting things rhythmically.

I want to live in the countryside with my boyfriend and have children. He’s also an environmentalist but lives abroad. Neither of us will fly, so we see each other rarely. On Friday afternoon I went up to the Sheffield documentary festival. By train. I don’t own a car and never will.

KITCHEN CONFIDENTIAL

I came home from Sheffield to find my kitchen was a state — I couldn’t let the police interview me at my house because I had mould growing on my washing-up. Frankly, world problems sometimes seem more solvable than my kitchen’s cleanliness.

The Age of Stupid was released on DVD last week

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