Lee Mead will be performing as Joseph
Performer Lee Mead is among some of London's West End stars taking part in a free two-day theatre festival.
He was to perform his starring role as Joseph in the West End Live event in Leicester Square on Saturday.
Organisers expect more than 150,000 people to turn out for the showcase of London's top shows.
There will also be performances by the King Lear musicians from Shakespeare's Globe as well as Jersey Boys, Divas, Dickens Unplugged and Mamma Mia.
Councillor Robert Davis, of Westminster Council, said he was confident everyone, regardless of age, would find something to enjoy.
"It offers a fantastic showcase for everything the West End has to offer from the worlds of music, film and of course, theatre," he said.
The event also features a celebration of 50 years of Lego where children can create their own structures.