Marcus found Karl just inside the airlock, sitting on the decking with several processor blocks in his lap. Eight blisters were slowly circling round him; two on the wall were stationary.

«Roman was almost right,» he datavised as soon as Marcus stepped out of the airlock. «Your exoskeletons were cleared away. But not by any butler mechanoid. Watch.» He lobbed an empty recording flek case onto the floor behind the blisters. One of them slid over to it. The green composite became soft, then liquid. The little plastic case sank through it into the blister.

«I call them cybermice,» Karl datavised. «They just scurry around keeping the place clean. You won't see the exoskeletons again, they ate them, along with anything else they don't recognize as part of the ship's structure. I imagine they haven't tried digesting us yet because we're large and active; maybe they think we're friends of the xenocs. But I wouldn't want to try sleeping over here.»

«Does this mean we won't be able to put sensors up?»

«Not for a while. I've managed to stop them digesting the communication block which the optical fibre is connected to.»

«How?»

He pointed to the two on the wall. «I shut them down.»

«Jesus, have you accessed a control network?»

«No. Schutz and I used a micro SQUID on one of the cybermice to get a more detailed scan of its electronics. Once we'd tapped the databus traffic it was just a question of running standard decryption programs. I can't tell you how these things work, but I have found some basic command routines. There's a deactivation code which you can datavise to them. I've also got a reactivation code, and some directional codes. The good news is that the xenoc program language is standardized.» He stood and held a communication block up to the ceiling. «This is the deactivation code.» A small circle of the ceiling around the block turned dark. «It's only localized, I haven't worked out how to control entire sections yet. We need to trace the circuitry to find an access port.»

«Can you turn it back on again?»

«Oh yes.» The dark section flared white again. «The codes work for the doors as well; just hold your block over the dimples.»

«Be quicker to use the dimples.»

«For now, yes.»

«I wasn't complaining, Karl. This is an excellent start. What's your next step?»

«I want to access the next level of the cybermice program architecture. That way I should be able to load recognition patterns in their memory. Once I can do that I'll enter our equipment, and they should leave it alone. But that's going to take a long time; Lady Mac isn't exactly heavily stocked with equipment for this kind of work. Of course, once I do get deeper into their management routines we should be able to learn a lot about their internal systems. From what I can make out the cybermice are built around a molecular synthesizer.» He switched on a fission knife, its ten-centimetre blade glowing a pale yellow under the ceiling's glare. It scored a dark smouldering scar in the composite.