David turned the device over and over in his hands, staring at it intently as if somehow the combination of touching it and staring at it would unlock its secrets. He turned to look at the unconscious man tied to his solitary chair, willing him to come to, so that he could question this mystery visitor as to the purpose of the smooth black disc with two unmarked buttons in the centre of one side.

It was cold to the touch, but only in so much as it was not warm – it was not chilled, just cold. The light seemed to slide off it, without reflecting, and it was that particular shade of black that really is just a lack of colour.

The man in the chair, from whom David had liberated the device, groaned and tried to raise his hand to his face, struggling against the rope restraining it. David slid the disc back into the pocket of his gilet and stepped across the room to be in his prisoner’s line of sight as he falteringly opened his eyes.

“So, what exactly were you doing, climbing in through my bathroom window?”