It was like a scene from an old movie. The famous diva falls ill hours before the curtain is due to rise. Her stand-in is told: "The show must go on."

She steps on to the stage of a packed, world-class venue - and brings the house down.

It all really happened to Susan Stacey.

As a teenager, she used to sing in front of a few hundred people in a seaside town.

Last week, she made her principal debut at the Royal Opera House, Covent Garden, in front of a capacity audience.

It was a proud moment for her family and friends in West Sussex.

Susan had served her apprenticeship in groups including the Worthing Operatic Society and Southwick Opera. Her friends knew this was the biggest moment of her career.

Susan, 37, was asked to step into the role of Odabella in Verdi's Attila when diva Maria Guleghina was forced to pull out with bronchitis.

Susan said: "They told me at 1pm and the performance was at 7.30pm. I was her stand-in and so was prepared to take over but it still happened very quickly."

Clapping the loudest as she took her bow was Susan's father, Mike Gorton, of Ham Manor Way, Angmering.

He said: "The moment I got her message to say she was making her debut, I rushed up to London. I wouldn't have missed it."

Mum Millie - who set Susan on the road to an opera career - missed the performance because she was visiting Susan's brother in America.

Susan said: "My mum was always very involved with the amateur opera scene.

"She was secretary of the Worthing Operatic Society, she ran the Worthing Music Festival for years and was also a board member of the Connaught Theatre.

"I remember going to the Pavilion Theatre to see Madame Butterfly and thinking to myself, 'I want to do that'."

She attended Sion Convent School in Worthing and got heavily involved with local opera societies in the evenings.

Susan said: "I was 12 when I made my debut with the Worthing Operatic Society and was 13 when I started with the Southwick Opera.

"It's nice because the opera world is a very close-knit community so I still keep in touch with some of the people I used to sing with and they know how I am getting on."

After leaving school at 17, Susan became one of the youngest senior vocal scholars at the Royal College of Music and won the Tagore Gold Medal for the most distinguished student in her final year.

Since then, she has appeared in productions around the world. Last week's performance could be the start of her rise to fame.