The former railway turntable shed, built in Camden in 1847, was played by artists such as Jimi Hendrix and the Doors in the 1960s, but closed as an arts venue in 1982. It will raise its curtains again next week for a National Theatre production. It will be transformed into a massive circus big-top for the National's production of Oh! What A Lovely War.
Co-producer Kenny Wax, of PW Productions, said: "It is a great venue. It is famous for having hosted circuses in the past and the building's ethos lends itself to the circus feel."
The play, which follows the fortunes of new recruits leaving home for the trenches in 1914, will run for eight weeks, following a successful regional tour.
Mr Wax said: "It is quite an experience. When we first started work it was just an outer brick wall and a concrete floor. No seats, no box office, nothing. Within 10 days we were sorting it out. We have the opportunity to put on first-class theatre and dance productions."
The rebirth of the Roundhouse has been made possible by the investment of one man, Torquil Norman, who, like Mr Wax, remembers the building in the "good old days".
Mr Norman, a former banker who founded Bluebird Toys, paid pounds 3m for the building on his retirement in 1996. It had been on the market for more than 10 years and was much in need of renovation. A trust was formed and Mr Norman set about launching the Roundhouse Creative Centre, a training venue for disadvantaged teenagers.
"During the late Sixties, Seventies and early Eighties, my family and I came to know the Roundhouse well. We went there often and our children learned music there. It is because of this love of the building, and the knowledge of how it can inspire, that we are determined to save it for a fulfilling future," he said.
Mr Norman's project - which should be finished in mid-2000 - is to include "superb facilities to give young people a once-in-a-lifetime opportunity to gain experience in the performing and visual arts", including theatre workshops, recording studios and multimedia equipment.
The pounds 21m renovation is being funded by the Norman Trust, with Lottery bids worth pounds 15m in preparation.
Oh! What A Lovely War opens 12 August. Roundhouse box office, 0171-420 0171; National Theatre box office, 0171 452 3000.