Now, as she pulled the dress on in front of the tiny mirror in the bare damp bedroom, it hung loose on her slender frame. She closed her eyes and tried to imagine that feeling of Mark beside her, pulling her into him for a hug. She couldn’t conjure it up. She was alone. She opened her eyes and stared at her reflection.

‘I can’t do this without you. Life . . . Everything . . .’ she said. Then, in her head, she heard what Mark used to say when he thought she was being over-dramatic: Get off the cross, someone needs the wood!

She laughed, despite her tears, saying, ‘I need to get a grip, don’t I?’

She wiped her eyes and reached for her make-up bag, untouched for months. She wasn’t a massive fan of make-up, but she applied a little foundation and lipstick and stared at her reflection. She’d been wondering why she was going today, defying her bosses again. She was doing it for Andrea, for Karolina, Mirka . . . Tatiana.

And for Mark. As with the girls, the person who’d killed him had never been caught.

The church of Our Lady of Grace and St Edward on Chiswick High Road was a dreary, industrial-looking building. Its square red brick structure was more suited to being a Victorian water pumping station than a church. In its tall plain tower, a bell tolled, but the traffic moved past unceasingly. A hearse gleamed in the grey morning light, the back windows packed with a rainbow of flowers. Erika waited on the opposite side of Chiswick High Road, watching between the traffic as the mourners filed in.

She could just make out, amongst the gloom of the front doors, Simon, Giles, and David. They were dressed in black suits and giving out the order of service. The mourners were well dressed, and much older than Andrea. As Erika watched, three former members of Tony Blair’s cabinet climbed out of a sleek Mercedes and were greeted warmly by Simon when they entered the church. A small group of photographers had been permitted to attend the funeral, and they were stationed on the pavement at a distance, their shutters clicking almost respectfully.

It was a story that needed no prompting or staging. A girl had died, far too young, and people were here to grieve. Of course, this wasn’t the final chapter. Marco Frost was due to stand trial in the coming months, and no doubt the complex and sordid details of Andrea’s life and death would be replayed, rehashed, and debated anew. However, for now, this was a full stop, the closing of one part.

A smart BMW pulled up at the kerb. Marsh and Assistant Commander Oakley emerged in black suits. Marcie and the Assistant Commander’s smart middle-aged wife followed behind, also in black. They moved quickly to the church entrance, pausing to talk to Simon and Giles, and to hug David, who seemed vulnerable, despite being taller than both Giles and his father.

The last mourners to arrive were Andrea’s mother, Linda, and the elderly lady with the hooded eyes. A limousine pulled up at the pavement and Linda bustled out and round to the opposite door, where she helped Diana from the car. Both she and the old woman, whose name Erika still didn’t know, were painfully thin, chic and elegant in black. Linda was swathed in a shapeless black tent, a dark woollen jacket, and she had a large wooden crucifix hung around her neck. Her mousy hair was neat, but looked as if someone had placed a bowl on her head and cut round it. Her face was devoid of make-up and she looked, even in the chill, to be sweating. The photographers took a keen interest and clicked away. Diana and the old woman bowed their heads, but Linda stared up at the cameras defiantly. Erika waited a few more minutes until it looked like the last mourners were inside, crossed the road and slipped into the church.

She took a seat at the end of a pew at the back of the packed church. A beautiful ornate wooden coffin rested on a plinth in front of the altar, decked in a spray of white flowers. The Douglas-Brown family sat on the front pew, and as the church organ petered out, Erika noticed Diana looking frantically around as the church hushed. The vicar, dressed in crisp white robes, moved to the front and seemed to look for a signal that it was appropriate to begin. However, Simon shook his head. He then leaned in under the brim of Diana’s huge hat, where they seemed to confer. Linda leaned in on the other side and joined the discussion. Erika realised what they were talking about: David was missing from the pew. Linda then got up, and standing at the front in full view of the congregation, just a few feet from Andrea’s coffin, placed a call on her phone. The vicar was now waiting awkwardly by the altar. Linda said a few words before being cut off. She tried the number again, and held the phone out to her father.

‘Linda . . . Linda,’ said Simon, beckoning her over. Linda huffed and stood her ground, before relenting and walking over. Her father took the phone and the conversation became quite heated. Erika couldn’t make out what was being said, but his angry tone reverberated around the church. The congregation was now shifting uneasily. The scene juxtaposed uncomfortably with the polished, flower-topped coffin. The murmur of Simon’s voice stopped abruptly, and Erika shifted in her pew to see what was happening.