‘Come in.’ Matt ushered him through to the living room. ‘Take a seat. This is Annabelle. My sister, Tessa. My brother-in-law, Mike.’

‘Nice to meet you.’ Rob sat in an armchair. ‘So, you have quite the situation.’

It wasn’t a question.

‘Yes,’ Annabelle said. ‘We do.’

‘And you’re definitely going to pay the— do what they’re asking?’ Rob said.

‘We are,’ Annabelle said.

‘And you want to track Annabelle after the handover?’ Rob said. ‘On the way here I considered a tracking device, but I think a drone makes sense. The kidnapper could find the tracking device easily, and I suspect they’ll look. They’ll be expecting it. So yes, a drone.’

‘Do you think it’s possible to follow me with a drone?’ Annabelle said.

‘It certainly is,’ Rob said. ‘There’s some pretty sophisticated kit out there. A lot of criminals use drones for exactly this purpose.’

‘In kidnappings?’ Matt said.

‘No. To follow cars they want to steal. Expensive ones. They follow them from the drone and watch the owner walk away, then they move in.’ He took off his jacket. ‘The drones are impressive. They can do around forty miles per hour, with a control range of three to five miles, depending on the terrain. Either way, you can control them from a distance, so no one would know you were there. And they can live-stream what they see.’

‘So you think we could make this work?’ Matt said.

‘Yes, with one caveat,’ Rob said. ‘They don’t fly for that long. Maybe thirty minutes. Forty max. So you have to hope that’s all you need.’

‘It will be,’ Matt said. ‘We’ll call the cops as soon as we have the kids. They can pick up Annabelle.’

‘It could work,’ Rob said. ‘But there are no guarantees.’

‘It’s all we have,’ Matt said.

‘How do we get one,’ Tessa said. ‘Can you buy them?’

‘Not these ones,’ Rob replied. ‘These are commercial drones. They’re also regulated; you have to register them with the Civil Aviation Authority. And you can’t just fly them anywhere. They’re geofenced – which means they won’t go into certain areas, such as near airports or prisons or other sensitive sites. You might need it to, if you’re following someone.’

‘So what do we do?’ Mike said.

‘Get hold of one,’ Rob said. ‘As well as someone who can operate it. They’re not the kind of things you can start using without any experience.’

‘Any ideas where?’ Tessa said.

‘I might know someone,’ Rob said, ‘who has unregistered drones which have been modified so they can go wherever their operator wants.’ He folded his arms. ‘She might let you rent a drone, and provide an operator. It won’t be cheap though.’

‘Who is she?’ Matt said. ‘Is she a—’