He headed through the underpass, breathing a little harder now from the weight he was carrying: am I getting out of shape? I can’t wait to get rid of this thing … and up the stairs on the far side: past some more “islands” of old preserved City wall, and then down again into the Tower Hill Underground station.

He pushed his train ticket into the turnstile before him, waited for the machine to spit it out again. The turnstile’s oblong vertical pads snapped open before him as he plucked the ticket out of the machine’s steel mouth, and Patel pushed through, along with about a hundred other people, making his way toward the stairs leading to the Circle Line and District Line platforms. There he would catch the last leg of his trip, the Tube train to Monument, and meet Sasha at the coffee shop at Eastcheap and Gracechurch Street: and she would take this thing off his hands … And arms, and shoulders, but particularly the hands, Patel thought, and headed down the stairs, stepping a little to one side so as not to be trampled by the people behind him. A direction sign just ahead of him said, Platforms 2 and 3, District and Circle Lines, west.

He headed for the sign, changing the bag again from left hand to right hand with a slight grimace as he went, and turned the left corner, toward the Tube platform—

Dark. Why was it dark all of a sudden? Power failure, Patel thought. Though where’s the light behind me? He turned—

The smell was what hit him first. My God, what is that ? Did the sewer break through in here or something—But there was no way to tell. He couldn’t see. Patel turned again, took a few hesitant steps forward. There was something wrong with the ground. It felt mushy—