Kirsty Young's castaway is the theatre producer, Sonia Friedman.

Acclaimed as the most influential producer in British theatre today, she has produced over 160 new shows. They include Funny Girl with Sheridan Smith, Jerusalem starring Mark Rylance, Benedict Cumberbatch's Hamlet, the record-breaking Book of Mormon and the musicals Legally Blonde, and Dreamgirls. Her productions both here and on Broadway have won numerous awards, including a record-breaking 14 Olivier Awards in 2014, and nine this year for Harry Potter and the Cursed Child.

Brought up in a creative, if unconventional, household, she left school at 16. After a stage management course at Central School of Speech and Drama, she cut her teeth at the National Theatre, worked with Harold Pinter, Richard Eyre and Tom Stoppard and then co-founded Out of Joint, a leading touring theatre company, with Max Stafford-Clark. She was named Producer of the Year for the third year in a row at The Stage Awards, and this year she also claimed number one spot in The Stage 100, a chart of the most influential people in British theatre, overtaking Andrew Lloyd Webber and Cameron Mackintosh.

Producer: Cathy Drysdale.

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