7:25 AM, Charing Cross Road, WC2

From the seat behind, all that can be seen of the woman on the bus is a large, shapeless black hood. It muffles her voice as she speaks on her mobile phone. The call ends, and the hood is pulled back to reveal a close-cropped, black head. A mass of needle-thin strands of plaited hair, black with sharp, bronze-coloured tips, flicks up from in front of her face. She places the wig squarely on her head and makes one tiny adjustment before the hood is pulled back up again.