‘Oh, yes. If you ever visit our city, you must see our famous Pleven Panorama – the largest structure of its kind in the world. Larger, even, than the Borodino Panorama in Moscow.’

‘Wonderful.’

Fry wasn’t sure she knew what a panorama was. She’d always thought it was one of those views of the countryside from the top of a hill that Ben Cooper loved so much. But that didn’t sound like what Georgi was talking about.

‘The Pleven Panorama tells a great story. The tragic destiny of our people, their dramatic fight, the compassion in the hearts of our Russian brothers. Within the Panorama, the spectator sees a charge of the Turkish cavalry, smoking shells, burning fires in the city, the Russian General Skobelev attacking a Turkish fortification. This attraction causes a great deal of interest in our city.’

‘As you said yourself, we don’t know much about Bulgarian history here.’

‘No, of course.’ Kotsev smiled. ‘But its construction might be of interest to you.’

He looked at her, as if expecting a reaction. But she still didn’t know quite what he was telling her.

‘I don’t think so,’ she said.

‘Ah, well.’

He began to walk on again, but Fry stopped him.

‘Georgi, who should we be looking for? If the Zhivkos and Simcho Nikolov came, then who else is here?’

‘Here?’ He laughed. ‘Here in the United Kingdom? You could start with seven thousand Bulgarian entrepreneurs. Including, perhaps, a one-legged roofer.’

The breeze was turning cool down by the river. Fry shivered a little, wishing she’d brought something warmer to put on. Apart from when she was at the office, she always seemed to make the wrong decisions about what to wear.

‘You’ve lost me,’ she said. ‘It was all making sense, right up until the bit about the one-legged roofer.’

Kotsev easily kept pace with her as she headed along the river towards the bridge. A few minutes’ brisk walking, and she could be back in her car with the heater turned up.

‘You don’t recall?’ he said. ‘A few years ago, your government introduced a so-called visa fast-track system. The purpose was to encourage entrepreneurs from Eastern Europe to come to the UK and set up business. Sadly, this system went badly wrong. Applications were not checked efficiently – many were not checked at all. Seven thousand unskilled Bulgarians and Romanians were allowed into your country on visas meant for entrepreneurs.’

‘Yes, I remember now. But the one-legged roofer?’

‘Ah, I bent the truth a little. He was actually a Romanian. But, you see, at that time there was an organized fraud in operation. One person submitted seventy identical business plans to support visa applications from Bulgarian individuals. They made a mockery of your entry control procedures, Diane.’

‘So you’re saying that pretty much anybody could have come into this country?’