In 1972, I found myself on the set of The Assassination of Trotsky, which starred Richard Burton as the Russian revolutionary. I was there to do ad hoc background shots, capturing rehearsals and that kind of thing. Joseph Losey, the director, would tell me all about Trotsky but I was more interested in Alain Delon, who played his assassin. He was very big at the time.

The film was being shot on location in a villa in Rome. Elizabeth Taylor wasn’t in the cast but one day, just as shooting paused, she suddenly appeared. There was no time to think. By chance, I managed to catch her and Burton sharing this moment. You can see the crew behind, setting up the next shot.

It was obvious something was going on. You could feel it – there was no great love between them. I don’t remember them even noticing the shot, which was taken at a distance from below. . If it had been a close-up of their faces, it would have just been two people looking not very nicely at each other. The body language brings it all together. They divorced a year or two later.

I had to be a fly on the wall. I’d hide behind people and avoid wearing bright colours, so as to pass unnoticed. Trotsky was the first film I worked on. I’d come late to photography. In the late 1960s, I was living in Rome with my family. My children were five and seven when my husband had a car accident. It was a close call. I remember sitting beside him in the hospital thinking: “My God, but for a few seconds, I would be a widow. I’ve got to do something. I’m quite artistic, though I can’t draw. What about photography?”

My husband created a dark room for me in the basement and I started fiddling about with his old Rolleiflex. A friend of mine was head of the Italian Olympic committee and he asked me to document sports centres he was setting up across the country. When people saw my pictures, they’d say: “They’re great.” But I didn’t believe them – it was too easy to say. So I decided to put myself to the test.

I got on a plane to London and, without an appointment, walked into the foyer of the Times and said: “I’ve got some photos. Who do I go to?” Fortunately, nothing was happening that day. Three days later, they published a full page of my photographs entitled: “Preparing for the 1980 Olympics.”

When I went back to Italy everyone was thrilled. They couldn’t believe it. I started working on films and went on to do countless magazine covers. At the time, I didn’t really think about being a woman photographer. I wasn’t an activist. But when my short film The Dress won a Bafta in 1985, a journalist asked me about it. I got quite annoyed.

I thought it was a silly thing to ask. Then I realised it wasn’t silly at all. When I started directing commercials, I’d be passed over for young men straight out of university. Then, in my mid-40s, I had a meeting with someone from a top Hollywood agency who said: “Yours is an interesting story, but there is a problem: you’re a woman and you’re not 20 years old.”

• Through Her Lens, by Eva Sereny, is published by ACC Art Books. An exhibition of her portraits is at Anemoi Art Gallery, London, from 14 September.

Eva Sereny’s CV

Born: Zurich, Switzerland.

Training: Self-taught.

Influences: “Bresson, and all the cinematographers I’ve worked with – Bertolucci, Fellini, Truffaut, Pollack, and of course Spielberg. I was very lucky.”

High point: “Getting the Bafta. I thought the world was at my feet then. Big mistake.”

Low point: “So many. Too many.”

Top tip: “Be ready for that moment. It will come only once.”