'The rest of you get into Sonral Street, he ordered. 'I'm going round the back to see if I can find another way down there.

'You're not going in alone? Kanseen asked. 'Edeard, there's three of them, and we know they carry blades.

'I'm just going to make sure they don't have an escape route, that's all. Come on, move.

He was faintly aware of his squadmates hurrying to the broad street beyond the alley. One of the thieves had bent down beside the small door, doing something to the first of its five locks. From what he could sense of the locks, Edeard knew he wouldn't like to try and pick them open. He concentrated hard, pushing his farsight through the city's fabric to map out the buried labyrinth of rooms and passages. In truth there were only three exits in addition to the one the trio were currently trying to break through.

Below that level, though, Edeard sensed the web of fissures which wove the city structures together. Several twisted their way up past the storerooms, branching into smaller clefts that laced the walls of the buildings above. He tracked back, finding a convoluted route that led to the street he was standing in. His third hand reached out, probing the fabric of the wall at the back of a tapering alcove between two shops. Nothing, it was as solid as granite.

Please, his longtalk whispered to the mind of the slumbering city. Let me in.

Something intangible stirred beneath him. A flock of ruugulls took flight from the roofs above.

Here, his mind pressed into the rear of the alcove. Something pushed back. Colourful shapes rose into his thoughts, swirling so much faster than the birds overhead. In his dazed state he thought they resembled numbers and mathematical symbols, but so much larger and more complex than any of the arithmetic Akeem had ever taught him. With these equations the universe could surely be explained away. They danced like sprites, rearranging themselves into a new order before twirling away.

Edeard gasped, struggling to stand up as his legs shook weakly. His heart was pounding far harder than it had been from his earlier run through the streets. He felt the structure of the wall change. When he peered forward it looked exactly the same as before, a dark-purple surface with flecks of grey stretching all the way up to where the curving roofs intersected three storeys above him. But it gave when his third hand touched it.

There were people on the street around him, strolling along. Edeard waited until a relatively clear moment, and stepped into the little alcove. Nobody could see him now. His hand touched the section of wall at the back, and slipped right through. The skin tingled round his fingers, as if he were immersing them in fine sand. He walked into the wall. It was a sensation his brain interpreted as a wave of dry water washing across him. Then he was inside. He opened his eyes to complete darkness. His farsight cast around, and showed him he was suspended in a vertical tube. Even without visual sight, Edeard instinctively looked down. Farsight confirmed his feet were standing on nothing.

'Oh Lady!

He started to descend. It was as though a very powerful third hand was gently lowering him to the bottom of the fissure which snaked away horizontally under the buildings. Yet he was convinced it wasn't a telekinetic hold. He couldn't sense anything like that; some other force was manipulating him. Oddly, his stomach felt as though he was plummeting even though he was moving relatively slowly.

His feet touched the ground. That was when whatever force had gripped him withdrew, leaving him free to sink into a crouch. When he touched the wall of the fissure, he felt a slick of water coating it. A rivulet was trickling over the toe of his boots — he could hear it gurgling softly.

'It's a drain, he said out loud, astonished that anything so fantastical could actually exist to serve such a mundane purpose.

Despite perfectly clear farsight, he patted round with his hands. The drain fissure was slightly too small for him to walk along it upright. Its side walls were about five feet apart. He took a breath, none too happy at the claustrophobic feeling niggling the back of his mind, and started to move forwards at a stoop.

The thieves had got through the locked door at the top of the passage. An impressive feat in such a short space of time. Two of them were descending the curving stairs to the door which sealed off the bottom, while the third stood guard outside. Edeard moved faster, navigating several forks along the drain fissure. He observed the thieves manipulate the locks on the second door, and go through. Then he was directly underneath the storeroom they were ransacking. The layout was distinct, the wooden racks laid out in parallel. Small boxes piled up on the shelves. A large iron box in one corner, with a very complicated locking mechanism. They were ignoring that.

Edeard looked up as his farsight pervaded the city's substance above him, a solid mass of rock-like material five yards thick. He concentrated. Closed his eyes — stupid but, well… And applied his mind. Again the equations rose from nowhere to pirouette breezily around his thoughts. He began to rise up, slipping though the once-solid substance like some piece of cork bobbing to the surface of the sea. Once again his stomach was convinced he was falling, to a degree which brought on a lot of queasiness. He had almost reached the floor, when he realized the thieves would sense him the second he popped up. Quickly, he threw a concealment around himself. Then he was emerging into the storeroom, with a weak orange light shining all around. The floor hardened beneath his boots.

'What was that? a voice asked.

Edeard was standing behind the rack at the back of the storeroom, out of direct sight. He held his breath.

'Nothing. Fucking stop panicking will you. There are only two doors, and the other one is locked. Now help me find the crap we came here for before someone senses us down here.

Edeard slowly walked round the end of the rack. He could see the pair of them, moving along a rack, taking boxes off the shelf and prising them open with some kind of tool. A quick look inside, and the box would be tossed aside. Most of them seemed to contain little bottles. Dozens of them were clinking as they rolled about on the floor.

'Here we go, the one in the hooded jacket announced. He'd just forced open a box full of tiny packets. One was opened to reveal a coil of metal thread. Edeard wasn't sure in the storeroom's low orange light, but it might be gold.

'I'll check out the rest, the other one said.

The one with the hooded jacked began stuffing the packets into an inside pocket.

Edeard dropped his concealment.

'What the fuck— Both thieves swung round to face him.

'Hello again, Edeard said. 'Remember me?

'Edeard! Kanseen's panicky longtalk reverberated in his skull. 'Sweet Lady, where've you been? We've been going frantic. How did you get in there?

'It's the little shit from the market, the thief in the hooded jacket spat. 'I fucking knew that ge-eagle was on the prowl. He reached inside his jacket and pulled out a long blade. At the same time his third hand tried to push into Edeard's chest for a heartsqueeze.

Edeard laughed as he deflected the attack. Then his own third hand slipped out and crushed the blade the thief was holding. The metal rippled, then warped into a slim bent spike. Edeard twisted the tip round into a U-shape. 'You're under arrest for theft and the attempted assault on a constable.

'Fuck! the other one yelled, he raced for the door.

'One coming out, Edeard's longtalk told his squadmates.

'Are you all right? Dinlay demanded.

'Never better. He hadn't taken his eyes off the hooded thief.

The man held up the ruined knife, and gave an admiring grin. 'Tough guy, huh. Are you smart with it? There's enough precious metal in here to make everyone happy.