A cast including Christian Slater, Ronni Ancona, Rob Brydon, Fiona Shaw and Samuel West are to take up the challenge of creating and presenting six plays in 24 hours to raise money for the Old Vic.

The actors will join writers and directors in what will be the fourth 24-Hour Plays gala on 11 November.

The event is to raise £125,000 for the Old Vic's New Voices programme which discovers and develops new artistic talent in theatre.

More than 3,000 actors, writers and directors aged 18 to 25 are currently in the New Voices network. They were involved in 45 shows of their own at last year's Edinburgh Festival, and another 70 productions around the country used them.

Kevin Spacey, the Old Vic's artistic director, said: "If you've done well in the business you wanted to do well in - and I've done better than I ever hoped - then you should spend an awful lot of time and effort sending the elevator back down."

He said the ripple effect of the programme was already showing: "You begin to see artists emerging beyond the walls of the Old Vic. There's a sense of people having a foundation and a home here from which to build their own careers."

He said the 24-Hour Plays were "a madness" for the participants.

"No matter what position a person might find themselves in fame, wealth or awards, it just levels the playing field," he said. "It brings everyone back to their first drama school audition."

Slater, who is starring in Swimming With Sharks at the Vaudeville Theatre, said: "It sounds fun and a great way to raise money for a great cause. I like the idea of discovering fresh new talent. I enjoy a challenge and hope the play we come up with will be interesting and exciting."

Ancona, who once worked in wardrobe at the Old Vic, said: "I have fond memories. It's a wonderful theatre and it does some wonderful work and needs to be treasured and nurtured."

Kwame Kwei-Armah, who has written and directed previous 24-Hour Plays and will perform this time, said: "I can't pull out because my ego wants me to do the triple, but I'm petrified.

"One of the guys who took part before said it's a blood sport. It's not until the audience sees the blood on the floor that they realise the swords are sharp.