King Lear, Almeida at King's Cross, London

Every inch a King - and a bit of a drip too

'The make-up! So much white cotton wool and my face looked as if a bicycle had been ridden across it repeatedly," recalls Jonathan Kent, the co-artistic director of the Almeida Theatre in London, of the time he played King Lear as a 16-year-old schoolboy in South Africa. His new production of the play, which opens at the Almeida's temporary home this week, starring Oliver Ford Davies, is a world away in every sense.

This is the seventh time he has worked with the designer Paul Brown since they met in 1993 on an Almeida production of Thomas Bernhard's The Showman. Their collaborations often have a long lead-time: it is about four years since their first chats about Lear. "We waste a lot of time talking about the production after next," says Brown, a Welshman who trained in theatre design at Motley, but only after attending university rather than art school because, "I didn't want people telling me what to do. I wanted to find out for myself." Since then he has worked mainly in opera.

Earlier Kent/Brown collaborations have included a spectacularly watery Tempest in the Almeida, for which Brown took advantage of the planned rebuilding programme to punch a hole in the roof and turn the stage into a lagoon. Both director and designer pay tribute to Aidan Gillen who, as Ariel, was suspended upside down and disappeared under water for longer than any normal non-spirit could survive. He was in no danger, of course, provided with a hidden air lock, but the discomfort was real enough. Brown says: "He had to swim along tunnels then run round the building in the cold." The water was heated, however. Kent jokes: "People used to go for little dips. There are photos of technicians lounging by the pool drinking pina coladas."

Before The Tempest, Ralph Fiennes starred in the Kent/Brown productions of Richard II and Coriolanus at the old Gainsborough Studios. Now converted into loft apartments, this building too presented the sort of opportunity which the pair relish. Most observers assumed that the ragged fissure in the back wall of the playing area, as if lightning had struck there, was a given. "No," says Kent. "We made it. Paul and I found the building together, but inside it was disappointing: two floors, lots of white paint. We burnt, chiselled, distressed it and drew the fissure on the wall." The result was a fitting environment for the historical sweep of the plays, with a built-in metaphor for a fracturing state – and with all the unexpectedness that Kent could hope for. "We like a challenge," says Brown laconically.

The Gainsborough stage was wide enough to suggest a whole kingdom in political turmoil. Earlier this year the pair collaborated on David Hare's version of Chekhov's Platonov, not at first sight an obvious choice for the almost equally vast space of the Almeida's present base in a former coach depot in King's Cross. "Chekhov demands verismo," says Kent, but, with Hare's agreement, they moved the action outdoors, thus providing opportunities for "distant" entrances and the creation of a large chunk of Russian country estate. Last week this won Brown the Critics' Circle 2001 Award for Best Design. Both Kent and Brown dislike – and avoid – scene changes carried out by stage-management: "It destroys the energy of the piece," says Brown. "The play must continue to speak without the intervention of outside forces interfering with the audience's suspension of disbelief," says Kent.

The script of Platonov calls for a train to chug across the stage – so one did (or seemed to). They insist that coups de théâtre are not, however, what they intend and that a design which becomes an end in itself, rather than an aid to expressing the play, is a failure. The Tempest risked losing this balance more than any other production – there was a temptation to worry just a bit about Ariel's lungs – but the strength of the acting and direction and the lack of interval (denying time to discuss distractions) maintained the unity of the production's concept.

So what of Lear? Kent says that the first image to come into his head was of "rain falling on a sofa in Lincoln's Inn Fields". The impression of an office or foyer remains, with panelling extending into the auditorium, and there is rain – plenty of it. "I like water," says Kent. "It blurs the boundaries." Lear provides a welcome opportunity for the aqueously inclined – a violent storm at its climax. More rain falls than you are ever likely to see again inside a theatre with a conventional roof. It last for 25 minutes. Kent and Brown have both been in a position to observe someone suffering from Alzheimer's, which may have influenced their decision to show the disintegration of a mind, the mind of a powerful person, in the disintegration of his surroundings.

There is no recognisable period. "This," says Brown, "is a clothed rather than costumed production. You build them with the characters. So different from opera when you might do 500 [costumes], a year in advance."

Kent adds: "This is a Lear on the unheroic side. The play is a flight towards love, through test, penance and suffering. Something does come of nothing." Much as a complete new world does whenever Kent and Brown put their heads together.

'King Lear', Almeida at King's Cross, London N1 (020 7359 4404) until 20 April