The exodus began from the private boxes. In a flurry of feathers and gold and silk, the bourgeoisie made hurried exits. Seeing them, the desire to withdraw spread into the upper tiers, where many of the nationalist protesters were stationed, then to the circles and stalls. The rows behind Léonie also, one by one, were emptying into the aisles. From every part of the Grande Salle, she heard seats snapping shut. At the exits, the rattle of the brass rings on their rails as the heavy velvet curtains were pulled roughly open.

But the protesters had not yet achieved their goal of stopping the performance. More missiles were hurled at the stage. Bottles, stones and bricks, rotting fruit. The orchestra evacuated the pit, snatching up precious music and bows and instrument cases, shoving through the obstacles of chairs and wooden stands, to exit under the stage.

At last, through the half-gap in the curtain, the theatre manager appeared on stage to appeal for calm. He was sweating, and dabbed at his face with a grey handkerchief.

“Mesdames, messieurs, s'il vous plaît. S'il vous plaît!”

He was a substantial man, but neither his voice nor his manner commanded authority. Léonie saw how wild his eyes were, as he flapped his arms and attempted to impose some sort of order upon the mounting chaos.

It was too little, too late.

Another missile was thrown, this time not a bottle nor some acquired object, but a piece of wood with nails embedded into it. The manager was struck above the eye. He staggered back, clutching his hand to his face. Blood spurted through his fingers from the wound, and he fell sideways, crumpling like a child's rag doll to the surface of the stage.

At this last sight, Léonie's courage finally deserted her.

I must get out.

Horrified, terrified now, she threw desperate glances around the auditorium, but she was trapped, hemmed in by the mob behind her and to the side, and by the violence in front. Léonie clutched at the backs of the seats, supposing she might escape by scaling the rows, but when she tried to move, she discovered the beaded hem of her dress had caught in the metal bolts beneath her seat. With increasingly desperate fingers, she bent down and tried to pull, tear herself free.

Now, a new cry of protest filtered through the auditorium.

“A bas! A bas!”

She looked up.

What now? The cry was taken up from every corner of the auditorium.

“A bas. A l'attaque!”

Like crusaders besieging a castle, the protesters surged forward, waving sticks and cudgels. Here and there, the glint of a blade. A shudder of terror made Léonie tremble. She understood the protesters meant to storm the stage and that she was directly in their path.

Throughout the auditorium, what little remained of the mask of Parisian society cracked, then splintered, then shattered into pieces. Hysteria swept through those still trapped. Lawyers and newspapermen, painters and scholars, bankers and civil servants, courtesans and wives, all stampeding towards the doors in their desperation to escape the violence.

Sauvez qui peut. Every man for himself.

Sepulchre by Kate Mosse £18.99 hardback, published by Orion on 31 October

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