Producers said that Simon Shepherd, who had been cast as Capt. Georg Von Trapp in the big-budget show, had withdrawn by mutual agreement with Lloyd Webber and his co-producers. Shepherd will be replaced by Alexander Hanson, who hoped to begin preview performances later in the week.
The show, due to open at London's Palladium on Nov. 15, has attracted publicity by using a reality TV show to cast relative unknown Connie Fisher in the lead role of Maria Von Trapp.
In a statement, producers said that following the first two preview performances on Nov. 3 and 4, Shepherd agreed with the producers and director Jeremy Sams "that his performance as Capt. Von Trapp was not working within the production and therefore he has withdrawn from the show."
Best known for playing a doctor in the British TV medical drama "Peak Practice," Shepherd was cast despite his relative lack of experience in stage musicals.
2"I can carry a tune but everyone else's singing is brilliant, so they did not need Placido Domingo for my role," he said in a recent interview.
Lloyd Webber's production is the first West End "Sound of Music" in 20 years.
Lloyd Webber has said he opted for the reality TV format after failing to sign movie star Scarlett Johansson to play Maria, the irrepressible novice who becomes matriarch to a musical clan in the Rodgers and Hammerstein musical.
The role, first played by Mary Martin in the 1959 Broadway success, was made famous by Julie Andrews in the perennially popular 1965 film.