Producers Andrew Lloyd Webber and David Ian developed a BBC TV talent show to choose a young British woman for the role of Maria in "The Sound of Music."
The Saturday night TV show "How Do You Solve a Problem Like Maria?" has drawn an audience of 6.8 million, Daily Variety reported.
Lloyd Webber has owned the rights to the popular musical for several years, but wanted a young woman to play Maria, who should be about 19.
Ten women were selected from 6,000 applicants. Vocal coaches, choreographers and acting teachers then worked with them, Variety said.
The winner will be chosen Saturday by popular vote. She will have to immediately start rehearsing for the six-month, six-night-a-week run at the 2,225-seat London Palladium theater.
Lloyd Webber and Ian are splitting the $7.1 million cost of production. If the winning Maria flops, they will lose their financial investment, the newspaper said.
Webber said the formula could be used to cast other shows. "But mark my words, if this comes off, you won't have heard the last of it," he said.