To pass the time, Most and Louis listened to some Czech jazz – solo piano music by a young pianist named Beata Hlavenková – followed by the BBC World Service. After two hours, the two men got out, opened the trunk, and removed the primary drone, a DJI S1000, bigger and heavier than the Phantom. The Phantom had a spec weight of about two and a half pounds, or just over a kilo, which meant that it couldn’t easily fly with a camera, a load of high explosive, and a detonator. The DJI could, but it was noisier than the Phantom, so they had chosen the Phantom for the initial surveillance and the DJI for the drop. With its eight arms, the DJI resembled a black-and-red spider. Most carried it to the edge of the lot, as far from the factory as possible. Then, while he watched nervously, Louis packed two pounds of C4 behind the drone’s camera before adding the detonator.

‘Have you done something like this before?’ asked Most.

‘You mean blow stuff up? What do you think?’

‘I meant with a drone.’

‘No. I’m a novice in that way.’

Most didn’t look any happier to hear this, and he already looked very unhappy indeed.

‘You should let me do it.’

‘I’m not going to put Luca Bilbija’s death on your conscience,’ said Louis.

‘Who said anything about a conscience? I just don’t want you to drop that thing on my car.’

Louis wasn’t worried about blowing them up so much as hitting an overhead wire or an unanticipated tree. Well, perhaps he was slightly worried about blowing them up, but he decided not to share this with Most. The DJI had a flight time of fifteen minutes, but they couldn’t risk bringing it close to the casino until Bilbija was on his way back to the house. That way, the engine noise from the convoy would cover the sound of the drone.

They returned to the vehicle and resumed their vigil, this time in silence. When Most’s phone pinged, it surprised them both.

‘They’re on the move,’ said Most, as he read the message. ‘They’ve asked for the Audi to be brought up, and there’s a police chaperone on the way. Five minutes, but no more than that.’

Louis started the propellers and they watched the drone rise. Both men held their breaths. Two pounds of C4 was a significant quantity of explosive, and the detonator was primed to go off as soon as it hit a hard surface. If the drone cut out, the explosion would leave a hell of a crater.

‘Shit,’ said Most, as the phone pinged again.

‘What is it?’

‘A problem. Some kind of disagreement at the door.’

‘Bilbija?’

‘Unclear.’