It's always fascinating to see how closures, refurbishment and architectural development shake up the life and activity of theatres. Both the Royal Court under Stephen Daldry and the Royal Exchange in Manchester were seriously reinvigorated by enforced exile: Daldry's Court in the West End during refurbishment, the Exchange elsewhere in the city after an IRA bomb in the nearby shopping centre.
Now the Lyric Hammersmith has formed a new resident company of twenty artists - ten actors, ten "creatives" - while the theatre undergoes extensive building work as part of a £16.5m capital project; this involves a major facelift and a two-storey extension to improve the Lyrics's work with young people and in the community.
So, the "Secret Theatre" will be perpetrated in the middle of a building site and over the year, through to next May, ten plays, some new, some classics, will be released into the repertory. No announcements will be made, no titles given, no Press nights fixed. The auditorium - which is unaffected by the changes - will be boarded over and a new flexible performing space created with seating for 200 people.
Sean Holmes, the artistic director, steamed into a Critics' Circle meeting last week to give us an impassioned preview, saying the whole season was inspired by the integrity and deep, forensic thinking about theatre by Edward Bond; and also by his own experience on co-producing Simon Stephens' controversial Three Kingdoms last year with a German director and a mix of British and Estonian actors.
Holmes believes he's working towards a "new type of theatre" and he's got Stephens right there behind him on the team, as well as playwrights Hayley Squires and Joel Horwood, both immensely talented, and a bunch of comparatively unknown actors including the versatile panto specialist Steven Webb and the extraordinary Leo Bill, soon to be seen in Mike Leigh's new film about the painter JMW Turner. Holmes' chief assistant director is rising star Ellen McDougall, while the team also includes a Korean-born designer, Hyemi Shin, and the Lyric's head of sound Nick Manning.
On paper at least, this all sounds like the sort of tight, close-knit ensemble that I've been advocating for years as a way of re-booting the RSC and possibly the National Theatre; those monoliths, for all the sporadic excellence of their work, have in fact become cultural conveyor belts. Redefining them would be like trying to turn round a liner in a tin bath.
Even the best of our fringe theatres merely do one play after another. The idea of ensemble, repertory, organic development of any kind, is quite literally foreign to the current British theatre, and Holmes's initiative could possibly become the most exciting thing to have happened for some time.
"The trouble with the RSC" Holmes says - he worked there as an assistant director - "and the National, is the tightness of the structures. You hardly see anything bad at the National, and that's sort of unhealthy." Lauding the German theatre, where nobody's happy, and the audiences are never tame or consensual, Holmes suggests its vigour and daring-ness is something to do with not wanting another war to happen. "Katie Mitchell, " he said, "understands the war now by having worked there a lot."
But can Holmes make our British sense of humour, irony and wit - low priorities in the German scheme of things - bend to a Teutonic model? I imagine he has no idea, which is all part of the experiment. "I have to be arrogant and humble," he says, but he's punching hard before he even comes out of his corner. His natural pugnacity, and great skill as a director, is now harnessed to the biggest challenge of his career.
The season starts on 9 September, all seats are £15, and anyone who lives or works in Hammersmith and Fulham can claim two free tickets to see Show 1 and Show 2 on the 5 and 6 September. It may all be terrible, but I doubt if it will be dull.
Meanwhile, Vicky Featherstone's Open Court continued last night with the latest piece of Surprise Theatre in the Theatre Upstairs, Sand by Nick Gill. This was a remarkable monologue about nuclear radiation and disaster delivered with stunning technique and unwavering intensity by the brilliant Irish actress Eileen Walsh.
I hope we have a chance to see it again, perhaps on a bill of the best of Surprise once Featherstone announces her first full season. Or perhaps it's essential to these projects that they come and go with the wind and somehow seeds are scattered throughout the Sloane Square theatre to produce fruit later on... that's what it feels like at the moment, and so does the uncertainty and excitement surrounding Sean Holmes' plans for the Lyric.