‘Mr Driscoll, if the swarm gets here before we leave, it isn’t going to matter a damn whether you find anything behind that wall or not.’

‘I know that, sir,’ Ty replied carefully. ‘But all I really need is a couple of hours. You know how important this is.’

The background hiss faded for a moment, and Ty guessed Martinez was consulting with Dan Perez, one of his senior officers.

‘Okay, here’s what I propose,’ said Martinez when he came back online. ‘The instant the swarm appears, the Mjollnir jumps straight out of this system regardless of whether you’re still on that rock or not. The same goes for everyone else who stays there, and the choice is strictly voluntary. I have to think of the crew.’

‘Nobody’s under any obligation to stay here and help me if they don’t want to,’ Ty replied, glancing over at Nancy and Curtis, ‘but I know I can do it a hell of a lot quicker if I have some help.’

‘What about the spiders?’ asked Martinez. ‘Have you considered whether you could run the entire operation from the bridge?’

‘No,’ Ty said straight away. ‘Look, the spiders help a lot, but they’re no good for fast, delicate work. They’re far too slow and clumsy for what we need to do here, and it’ll end up taking much longer than it should, if we have do the entire thing by tele-operation.’

‘Nathan’s right,’ Ty heard Nancy say. ‘The spiders are fine for this kind of work only if there’s no time constraint.’

‘Yeah, I agree,’ said Curtis. ‘The more of us down here who know what we’re doing, the faster we get everything done and get back out. The last of the detectors is now in place, so we should be able to pick up a video feed straight away.’

‘That’s fine, Curtis,’ Martinez replied. ‘But every analysis says we don’t need more than two people down there, so I want you and Anton back here on the frigate. Nancy and Nathan, I spoke to Cesar. He’s going to remain on the surface with a fast launcher. Just don’t take one second longer than you have to.’

‘No problem.’

Martinez cut the connection.

‘Detectors?’ asked Nancy.

‘Muon detectors,’ Curtis explained. ‘We stuck them around the surface of the asteroid. They pick up traces of decaying cosmic-ray particles, so we can build up a picture of whatever’s inside there.’

Ty nodded. ‘Did you bring the screens?’

Curtis passed a rolled-up video monitor over to Ty, who opened and smoothed it against one wall, holding it flat there while Curtis retrieved a hammer from a spider’s toolbox and nailed the monitor to the stone at all four corners.

Ty stepped back and studied the chiaroscuro of greys that appeared on the monitor a few moments later, quickly resolving into a map of the asteroid’s tunnels and chambers.