Julie Walters and Willy Russell: how we made Educating Rita
Julie Walters: 'I was so terrified on opening night, I was taking Valium backstage. I was shocked when people laughed'This was born of desperation. It was 1979 and the RSC had asked me to write something for a season of experimental work. Their London home was in what's now the Donmar Warehouse. When I went in, I thought: "Oh, it's one of those brick-box, black-drapes places. There's no way I'm going to write that ki…