Before they had time to voice any alternative theories, a PC approached Tom with an envelope. ‘Tox results,’ he said, his eyes lighting up. They were praying these might give them something to work with, and they had been rushed through the system.

But Tom didn’t have time to look at them. His phone rang. ‘Tom Douglas,’ he answered. ‘Yes indeed, ma’am. I’ll come right away.’

He rolled his eyes so that only Becky could see, and she tried to hide her smile. Tom had been summoned from on high, which probably meant his boss had something to say about their current investigation.

Tom’s frustration at the lack of progress on the case was echoed by Detective Superintendent Philippa Stanley in what he considered to be an unnecessarily long meeting. She was scathing about Tom’s attempts to solve the case and left him feeling disgruntled with himself for not having better answers to her criticisms.

‘With the increased threat of terrorism hanging over our heads here in Manchester and more than one gang-related murder on your files that remains unsolved, I’m not sure I understand your obsession with this particular case.’ Tom opened his mouth to speak, but Philippa continued: ‘And don’t tell me it’s your famous gut at work again. That is what you were going to say, isn’t it?’

Tom looked at the woman with whom he had worked for several years and remembered how well she knew him. As a new detective – like Lynsey was now – Philippa had reported to Tom, but she had risen rapidly and determinedly through the ranks until the tables had turned, and she was now Tom’s superior officer. Only once, on their very first case together, had Tom seen a chink in her armour. Since then she had cultivated the air of a perfectly poised professional in her ubiquitous navy-blue suit and white blouse, with her hair in a dark bob that never seemed to get any longer or shorter.

Despite her cold, aloof manner, Tom knew another side of her. But sadly she knew another side of him as well, and she had guessed right – he had been about to claim that he had a feeling about this case.

‘It’s an unusual case, Philippa. We don’t know who she is or precisely how she died, but if Amy Sanders and Jumbo Osoba are right about the exit bag and the fact that she had help, we need to find out if she was murdered. If so, who by? If it was assisted suicide, who helped her? The tox results came in just before I got your call. I haven’t had a chance to analyse them in detail, but I had a quick scan in the lift and read them a bit more thoroughly while I was waiting outside your door.’