Preview: Happy Days, National Theatre, London

Glad to be worked into the ground

The image of Winnie buried up to her waist, and then later her neck, in scorched earth, under a blazing light, and woken by a piercing bell, while assuring her husband, Willie, that this is one of her happy days, is one of Samuel Beckett's most powerful theatrical symbols. For Deborah Warner's new production of Happy Days at the National's Lyttelton Theatre, the set designer, Tom Pye, is charged with creating the mound.

"I have used a mixture of all manner of real and fake materials for the earth," says Pye, "including a lot of polystyrene, grass, sand, gravel, and fake rubber crumbs, which look like earth, along with timber and technical engineering."

Fiona Shaw, who plays Winnie, will spend 31 performances sitting on a special seat under the mound for the duration of the play. The experience will be similar, Pye says, "to sitting on a long-haul flight, so we must try to make it as comfortable as possible for the actress. We have had to work out the exact spot Fiona wants to be in, as once she is locked in, we can't change it. We have lowered the Lyttelton's stage. Now everybody can see her and she has good control of the house."

Pye worked in television and film before discovering that he preferred opera and theatre design. His recent work ranges from the digital-video designs of Sinatra at the London Palladium to Complicite's acclaimed production of Measure for Measure at the National. He has previously collaborated with Warner on productions of Julius Caesar and The Turn of the Screw.

Pye has researched previous productions of Happy Days to see how the poetic image of the mound of earth has been dealt with. "A mound of earth can be a thousand things," he says. "Hopefully, the audience will identify our earth mound with global warming, Iraq, and the Middle East, yet they will not be able to pin it down," says Pye.

In rep to 1 March (020-7452 3000; www.nationaltheatre.org.uk)