Olympe swallowed, tucking a curl of hair behind her ear. She did it deliberately, as if savouring the freedom to touch her own face, attend to her discomfort.

‘I don’t know who this duc is or why he wants me. So, no, I don’t want to go to him. I’m sick of people treating me as though I’m their possession. I want to choose my own fate. I want to find my mother. And I want to be free.’

Camille smiled.

‘Okay, then.’

She wasn’t going to let herself be used. She would rescue Olympe, not because the duc had hired her, but because Olympe needed help and that’s what the battalion did. If the duc wanted Olympe, then she was going to make it damn hard for him.

‘Come on.’ She took Olympe’s hand. ‘Let’s get out of here.’

The explosion shattered through the prison when they were only halfway to the exit. The stone wall burst open like a tear in rotten fabric, and chaos erupted. Smoke swirled from the cellars, and above, a wooden gantry sagged and snapped, sending soldiers and prisoners crashing to the ground.

Olympe’s hand squeezed Camille’s so tightly that she gasped in pain. The explosion must have spooked her – but Olympe was focused on the other side of the courtyard.

‘He’s here,’ hissed Olympe. ‘Docteur Comtois.’ She pointed to a thin white man wearing a drab black suit and a tricolore cockade marching swiftly along the remaining length of the gantry. If Olympe hadn’t panicked at the sight of him, Camille would have thought him completely unremarkable. ‘We have to go, he can’t see us.’

But it was too late. The docteur had stopped, frowning. Silently, he held out his arm and pointed at Olympe. A unit of soldiers poured towards them. Olympe shivered, and for a second Camille worried she was about to crackle with that electric charge. But she held herself in check.

Camille hauled Olympe through the chaos, changing direction. The only way left unblocked by rubble or soldiers was a staircase leading to the roof. From there they had a chance of escape across the rooftop of the neighbouring Tribunal building. Lungs burning, they tumbled onto the expanse of sloping tiles. Rain had started to spit from pale clouds, making the tiles slippery. Camille’s chest was tight, spasming with the need to cough. She forced herself on. She wouldn’t let her own weakness get in the way. Not when victory was this close.

They were almost across when a soldier poked his head through a skylight ahead. Camille swore. The soldier clambered out, followed by another, and another. She turned to go back the way they’d come, but more soldiers had followed them.

‘What’s your plan? What do we do?’