Callum Brierley

Callum Brierley is 39 and has spent more time hanging from ropes than many people spend sitting. Born in Slough, the son of an aircraft mechanic and a hairdresser, he left technical school at 17 and joined a facade-cleaning company, where for six years he washed glass on City towers, two hundred meters above the ground. A fall made him trade the rope for the forklift, and for four years now he has been the warehouse's day-shift supervisor.

He lives in a one-bedroom apartment in Slough, on the fifth floor of a new building, from which he watches planes descend in a line to the Heathrow runway. The living room has a leather sofa, a big television and a shelf of photographs of tall buildings seen from the side, taken by him in his facade days. In the hallway, a squeegee with a telescopic handle, which he no longer uses but doesn't throw away.

He is thin, with strong shoulders, an angular face, a short trimmed red beard and auburn hair shaved at the sides. He has a thin scar on his chin, forearms with prominent veins, and wears a gray work jacket with an orange reflective vest, his badge on his chest and a chunky sports watch on his wrist. He is practical, quick with answers, talks about the warehouse like someone who runs it and treats the police with rehearsed patience.

About the job, he says he supervises the day shift and that before that he spent six years hanging from a rope. He explains the alarm: motion sensors on the floor, covering up to about ten feet of height, and above that nothing, because nobody ever thought of a thief coming from the ceiling. Of the night guard, he observes that his car vanishes from the yard in the small hours, between midnight and 2, as he sees from the gate when he arrives early, and that the rounds in the book match too neatly.

Callum knows the supervisor who arranged the trunks on Friday is the first remembered when they turn up empty. When the detective says he came down through the skylight and took the books, he twists the sports watch on his wrist and answers that he supervises cargo and doesn't steal it, and that he will only speak in front of the union lawyer. A professional's rebellion, or a rehearsed patience that ends with no answer ready: the watch turns the same.