Had anyone heard? She wiped the sweat off her face with rust-stained hands and rubbed her hands down the sides of her pant suit. Then she reached for the top bolt. No good. She had to haul back the ladder and climb up before she could reach it. Had anyone touched the bolts since they were pushed across in the Beginning? She could feel herself trembling, her excitement tearing through the psychic fabric of the Web like shears through synthetic. If she wasn't careful someone would realise what she was doing and catch her before she could get away. She took a deep breath and tried to quieten her unruly mind.

The second bolt slid across. She heaved the ladder out of the way so hastily that it began to topple and she only just grabbed it in the nick of time. Again she stopped and listened, her heart thumping. No one seemed to have heard.

All right, Ruth. Here goes. She turned the door knob and pulled. The hinges creaked and the Door swung open reluctantly. Beyond it, stretching into darkness, was a bare concrete passage.

Not in the dark, she thought. I can't. Her hand fumbled against the inner frame and found a switch. As if by magic the passage sprang into whiteness. She could see straight ahead for about two hundred metres before the line of lights curved out of sight to the left, beckoning her forward to see what lay around the corner.

She shut the Door carefully behind her and took a deep breath. The smell of damp and dust surrounded her. She walked forward, her footsteps echoing loudly. She found herself tiptoeing. What was around the corner?

Another hundred metres or so of whitewashed passage ended in a blank wall. Was it all a joke? Was there no way out of the Ark? But that was crazy. No one would build an underground passage going nowhere. Her ancestors had to have come through this passage, once the Dome had been sealed over the City. And if the passage led nowhere she would have to go back. To face Patience and Angela and the others ...

She ran along the last fifty metres, her footsteps echoing loudly. But it was all right. Once she reached the end she could see the ladder set into the left hand wall. It led up through a round tunnel into darkness above.

She began to climb. Paint flaked off against her hands and rust stained her palms red. How far was it? Not far, she told herself. The Door was only one floor underground. It couldn't be more than three or four metres, could it?