He pressed on, edging sideways when the walkway wriggled precariously between two bulkheads that almost touched one another. Another metal ladder followed, so rusty that it felt like it would fall apart under his weight, before he found himself on a service platform at the rear of a hab-tower, nine storeys up, overlooked by a facing wall studded with more shuttered windows.

He moved over to a low railing on the far side of the platform and looked out across a jumbled landscape of overlapping rooftops, crosswalks and hidden courtyards, fenced in on all sides by the higher street-facing blocks. This was a view few would ever see, unless they lived in one of the inward-looking hab-units and dared to pluck at their shutters. The vantage had been picked out after a study of the cartographs stored in the Bastion’s archives, and for once they hadn’t proved outdated or inaccurate.

Zidarov checked he was alone, then knelt down, settling against the railing, and brought up the ranged auspex he’d taken from the armoury. He rested it on the railing’s top, and adjusted the sights.

Borodina had given him a list of known or suspected Yezan cell locations. This was only one of them, and yet from the start he’d had a feeling about it. The Vidora liked to operate as far away from attention as possible, unlike some of the flashier cabals who enjoyed flaunting their status. This site was perfect for them – a long way back from the street front, embedded deep in a district where even sanctioners went watchfully, surrounded by underfed citizens who were scared of everything and knew how to keep silent.

He calibrated the auspex, adjusting for the murk, and swept the viewfinder out to the designated coordinates. The rooftops blurred and zoomed, before clarifying onto one building at the centre of the cluster. He made out a narrow courtyard at ground level, steeply overlooked and very dark. He saw a patchwork of pressed-metal walls on its far side, the kind of thing a prefab storage unit would be made of, and a locked pair of slide-doors.

He settled down for a wait. He studied the details, moving the auspex gingerly to maintain focus. The place was all nondescript enough, with nothing to detain a casual glance. If you knew what to look for, though, some things stood out. The windows on the storage unit were shuttered like all the rest, but more expertly, with no chinks or gaps around the edges. Some work had been done just under the roofline – housings for remote sensors, tripwire security, things like that. Three big air filters had been fixed to the roof tiles, all whirring away. It was pretty robust, all told. He wondered why they needed so many filters.