(..) We need to find a place in the city where all five of these things intersect. Chalk, asphalt, brick dust, vegetation. What - chocolate?! I think we're looking for a disused sweet factory. We need to narrow that down. A sweet factory with asphalt? No, too general. Something more specific. (..)

(..) So have I! Homeless network, faster than the police, far more relaxed about taking bribes. John. Rhododendron ponticum. Matches. Addlestone. What? A mile of disused factories between the river and the park, matches everything. Right, come on. Come on! OK, you look over there. Look everywhere. (..)