Sam Walters, the longest serving artistic director in the UK, has announced the 40th anniversary season at the Orange Tree in Richmond, London's only permanent in-the-round theatre.

The first production will be the UK premiere of The Conspirators by Václav Havel, a writer with whom the venue has a long association.

Speaking to Whatsonstage.com, Sam Walters said: “Our involvement with Václav Havel and Czech politics is perhaps the most exciting part of our 40-year history, so it is highly appropriate that we are opening our 40th season with a Havel play written in 1971 - the year we opened in the room above the pub.”

Running from 2 September to 1 October 2011 (previews from 31 August), The Conspirators, which Walters himself directs, explores a post-revolution society. The dictator has fled. The new government is in power. But the prime minister’s secretary is under arrest and there are demonstrators on the streets and concern that the ideals of the revolution are about to be betrayed.

It's followed by a new play written and directed by David Lewis (who has had six plays produced at the Orange Tree previously) called How to be Happy (opens 7 October), centring on a former happiness guru struggling through the minefield of middle age.

The anniversary season concludes with revivals of James Saunders' 1963 play Next Time I'll Sing to You, directed by former Hampstead artistic director Anthony Clark (opens 11 November), and 1905 comedy The Charity That Began at Home by St John Hankin, directed by Auriol Smith (opens 16 December).