Initially, the door was knocked on quietly and without fuss. No response. They knocked again, listening through the closed door with a high-sensitivity microphone. The officer using it pulled away from the door, pointing to the other side of it, then giving a whirling signal with his forefinger. Someone was inside the apartment and choosing not to answer the door. Ava nodded her consent to move to the second phase of attempted entry.

‘Police, move away from the door!’ the officer at the front shouted loudly.

Ava covered her ears as an Enforcer was used to batter the lock section of the door. It gave way on the first ramming. The door flew open, slamming against the wall behind it, and a stream of bodies disappeared into the lounge area.

A new voice began shouting before Ava could even reach the front door, then there were yelled instructions and the heavy, dull thump of a body hitting carpet. A caution was given. The response was a stream of expletives followed by commands to stop struggling. Ava went in.

RJ Bott was face down on the floor thrashing his legs uselessly as officers restrained him. She looked around his flat, drinking in the chaos: three half-empty cereal bowls decorated the floor. There was nothing on the walls except a large TV screen. The furniture was mismatched and threadbare, and the only literature to be seen was a tatty porn magazine that no one in their right mind was going to touch without heavy-duty gloves and a litter picker stick. The back windows looked out into a shared garden area surrounded by trees, but only through the cracks between the blackout curtains held up with gaffer tape.

‘I’m guessing he doesn’t use the place for romance much,’ Tripp said, pointing to a pair of underwear left over the back of the armchair, obviously worn.

Ava looked away. Every crime scene, every house she’d raided, left a stain in her head. The man on the floor protesting something about human rights and access to a lawyer may not have been expecting visitors, but that didn’t excuse the foulness of his living space.

She walked into the bedroom – a mattress on the floor with bedding that was stained in a manner resembling bodily fluid tie-dyeing – and caught sight of a collage in the mirror in front of her. For a moment she didn’t want to look. The last time she’d seen so many carefully displayed pictures of dead bodies was when she’d been studying a police course in forensic pathology.