The Bolshoi has been threatening to disintegrate for years. The original theatre was built between 1821 and 1825, then destroyed by fire and rebuilt in 1853. In 1920, the building started to shake during a performance. They fixed that with a concrete base beneath the floor – which affected the acoustics. In 2002 a second world war bomb was discovered beneath one of the theatre’s entrances. But it wasn’t until last year’s closure that anyone realised exactly how serious the situation was. The foundations had sunk by 20cm. There were areas of brickwork that, when the restorers tried to take them apart, crumbled to the touch.”