Ada looked round in confusion. They should still be in the part of the cellars where the prisoners were kept. Had she taken a wrong turn? She ran over the prison plans in her head. They’d gone left at the bottom of the stairs, to go north. Only, the stairs had twisted as they’d gone down. Left had taken them south, away from the chapel and further under the prison.

‘It’s the arsenal.’ Guil was examining the array of barrels, running his thumb along the seals and sniffing it.

Suddenly, the strong smell of gunpowder made sense.

There had to be more than twenty barrels stacked around the cramped room. It was divided by the remains of a wall that had once split off an inner room, a break where the door had once been. The only light came from a series of wells bored into the ceiling. The soldiers had stopped hammering on the door – someone must have gone for a key. It was only a matter of time before they returned.

They were trapped.

She’d made another mistake. First the balloon, now this. Camille trusted her and she kept letting her down.

‘Well, this plan has gone arse-backwards.’ Al pushed his ash-blond hair behind his ear. ‘I don’t know why Camille lets us out of the house.’

‘Pity, in your case,’ replied Guil. He had set down the useless musket on top of a barrel and started picking through the contents of the room. ‘If I can find some bullets, we might be able to fight our way out.’

Ada shook her head. ‘In a room full of gunpowder? We can’t risk a bullet hitting one of the barrels. It would take out a whole wall.’

Al shrugged. ‘I don’t know. Blaze of glory, and all that. Worse ways to go, these days.’

But Ada wasn’t paying attention. Something had caught hold in her mind. Take out a whole wall – yes, it could. They would have to be extremely careful. Try and isolate one area as much as they could. Find some sort of shelter.

It would have to be perfect. She couldn’t afford to make another mistake – not when her friends’ lives were at stake.

‘I might have another plan. It’s a really, really bad plan.’

‘There are no bad plans,’ said Guil. ‘Only badly implemented ones.’

Al gave them both a dark look. ‘We’re living in a city that cut off its king’s head. I think anything goes at this point.’

Ada reached into her pocket and pulled out the flint and tinderbox she’d used to light the brazier in the balloon.

‘If we can’t go out of the door, we could always make another one.’

Guil and Al looked at her for a moment, silently.

‘I thought you were the one against going out in a blaze of glory?’ said Al.

‘It does seem … risky,’ offered Guil.