I pick my way between the devastated walls of ruins, trying not to brush against them because, whenever I do, they give out muted gunshots and screams, as if whatever conflict murdered this city has soaked into the remaining stonework. At the same time, I'm moving quite fast, because there is something following me, something that has no such qualms about touching the ruins. I can chart its progress quite accurately by the tide of gunfire and anguish swelling behind me. It is closing. I try to speed up but there is a tightness in my throat and chest that isn't helping matters.