Concern is growing in the Russian ballet world over the fate of leading choreographer Dmitry Bryantsev, a month after his mysterious disappearance.
Tough in rehearsal, Bryantsev is known for his fine sense of humour
Police in the Czech Republic have begun a search for Mr Bryantsev, last seen on 28 June on a private visit to Prague, Russia's Itar-Tass news agency reports.
Mr Bryantsev, 57, has played a key role in Russian dance as artistic director of Moscow's Stanislavsky Ballet.
He once told BBC News Online his work aimed to reflect his country's mood.
Colleagues in Moscow have daily been asking the Russian embassy in Prague for updates on the search for Mr Bryantsev.
They first suspected something was wrong when he failed to fly back in Moscow as scheduled on 30 June.
Czech police then discovered his luggage and mobile phone, switched off, in his hotel room in Prague. So far they have only established that he never left the country.
Mr Bryantsev had arrived in Prague on 25 June. The reason for his visit has not been reported but Russia's Novyye Izvestia newspaper says it appears to have been "entirely personal in character".
Vladimir Urin, the Stanislavsky's director general, said the whole company was anxiously waiting for news of its senior choreographer.
"Until we get official conclusions, we'll keep waiting for him because fantastic things happen sometimes," he said this week in Moscow.
Bryantsev has led the Stanislavsky Ballet since 1985
In December 2001, during his first season with the Stanislavsky in London, Mr Bryantsev told BBC News Online of ambitious plans to rebuild the company's home venue, the Musical Theatre in central Moscow.
He also outlined plans for a clutch of new ballets including an exuberant piece for children, The Circus Is In Town, which has since premiered.
Returning to London in December 2003 with his productions of The Nutcracker and Swan Lake, he appeared in excellent spirits, says BBC News Online's Patrick Jackson.
He says the choreographer was brimming with optimism about the future of his company, which dates back to the 1920s and whose best work rivals that of the better-known Bolshoi Theatre, a few streets away in Moscow.