Alex had just returned from school and was watching The Simpsons in her bedroom when the phone rang. She distinctly recalls the first thing he said. “Hi, it’s David Walliams . You know, off the telly!” It was January 2004. Alex was 15 and studying for her GCSEs. Walliams was 32 and a rising star with the comedy sketch show Little Britain.

A few days earlier, Alex had been to a fan event where Walliams had signed autographs as his character Lou. Wearing a frizzy wig and a black leather jacket, he looked up at Alex as her mother took a photograph. As she approached Walliams, Alex remembers him saying: “You’re a very attractive lady.”

With ambitions of becoming a comedy writer, Alex says she gave him some printouts of scripts she had written. She included a cover letter with her contact details, but she did not expect him to get in touch.

When he did, she was so excited that immediately after the call she made a record of the conversation in youthful scrawl across four sides of A4 paper.…