‘I don’t know,’ said James. ‘I’ve been trying to think. We all rode down from the dam together in one of the railway cars.’

‘And what did you talk about?’

‘The dam,’ said James, and an awful realization struck him. ‘He’s going to try and breach the dam.’

‘He wouldn’t,’ said Amy. ‘All these people…’

‘What would he care about that?’ said James.

‘He wouldn’t,’ Amy repeated quietly.

‘We have to stop him,’ said James.

One of Zoltan’s men ran past. There was a crack and he toppled over into the fountain. His blood quickly stained the pool and in a few moments the curtain of cascading water had been turned pink. James and Amy cringed back against the central support. They both wanted to get out of there as fast as they could now.

‘What are we going to do?’ said Amy.

‘We could try and go up to the dam on the railway,’ said James.

‘Shall we risk it?’ said Amy, who had evidently got her courage back.

The firefight had moved on. The last of Zoltan’s men had fled inside the palazzo, with Ugo’s guards following.

‘Well, we can’t stay here all day,’ said James. ‘Come on!’

They darted out of the safety of the fountain and sprinted across the piazza, their wet feet slipping on the polished marble. As James ran his whole body was tensed, waiting for a bullet to hit him, but they made it unhurt and he glanced quickly back. There was nobody around.

They climbed aboard the railway car and pulled the doors shut behind them. For a while they lay exhausted on the floor in a slowly spreading pool of water. Then James sat up and saw a terrified guard crouching in the shadows at the other end. He had a tommy gun in his hands but it was shaking all over the place and he obviously had no desire to use it.

James yelled at him. ‘Get out! Just go.’

The guard didn’t think twice. He jumped up and bolted away like a startled rabbit, leaving his gun behind.

James studied the car’s controls but could make no sense of them.

‘How does it work?’ said Amy.

‘It’s a counterweight system,’ said James. ‘The two cars are connected by a cable that winds around a big drum up at the dam. The car at the top is filled with water until it’s heavier than the one at the bottom. Then it rolls down the slope and pulls the other car up. Once it reaches the bottom it empties the tank and the process is reversed.’

‘How do you empty the water out, then?’

‘It’s one of these levers,’ said James and he started to yank and twist everything he could find. Amy joined him and at last they heard a flushing sound as the tank below was emptied into the drain.