The women scowled at him and turned back to their conversation.

‘No one seems to have a sense of humour this morning,’ muttered Woolf, opening his newspaper and biting into a Danish pastry.

When Erika arrived in the incident room, everyone was present, sitting in silence. Marsh was waiting at the front, drinking a cup of coffee.

‘Ah, Erika, please take a seat.’

‘I thought I was briefing the team this morning, sir?’

‘So did I, but things have changed. Please, sit down.’

Erika perched on the long row of tables at the back, where the row of printers was unusually silent.

Marsh began, ‘Last night, Dr Isaac Strong, who has worked on this and several other investigations with us as our forensic pathologist, was charged with the murder of his partner, the author Stephen Linley.’

Marsh paused as the officers absorbed this.

‘This has put us in rather a complicated situation. Much of the forensic evidence from our investigation into the deaths of Gregory Munro and Jack Hart has been processed by Dr Strong, and in two cases, his findings helped us to profile the killer. The way that Stephen Linley was murdered shares many of the same traits as the murders of Gregory Munro and Jack Hart. Stephen Linley was found with high levels of flunitrazepam in his blood. He was also suffocated using the same type of “suicide” bag, but in this instance he appears to have fought with his attacker. The post-mortem and toxicology have shown that Linley was a regular user of recreational drugs – benzodiazepines and Rohypnol, the brand name for flunitrazepam – and had a higher tolerance of such substances. The only forensic DNA evidence found at the scene is male.’

Marsh paused again to let the officers in the incident room take this in, then he went on. ‘Stephen appears to have enjoyed many sexual partners, and last night he’d been to a gay sauna. CCTV shows he was at the Chariots gay sauna in Waterloo from 6 p.m. until leaving at 10 p.m. In addition to this evidence, the murder of Stephen Linley was on the Bowery Lane Estate, EC1, which puts this firmly in the jurisdiction of the City of London Police. So, not only was it not on our patch but it is outside the jurisdiction of the Met.’

‘Sir, surely they don’t think that Isaac Strong is the serial killer?’ asked Erika.

‘Can I finish, please?’

‘I would have appreciated you briefing me beforehand, sir. I am the SIO on this case and now I’m hearing all of this information for the first time.’

The officers in the incident room shifted uncomfortably in their seats.

‘Erika, I have only been briefed about this by the Assistant Commissioner in the past twenty minutes,’ said Marsh. ‘May I please continue?’

‘Yes, sir,’ said Erika.

‘Dr Strong was found at the scene. He was initially held for routine questioning – he says he discovered Stephen’s body. Then results started coming back from the crime scene. There were a large number of photos on Stephen Linley’s laptop, and a positive identification was found for a JordiLevi.’

‘He was the rent boy we interviewed. He was at Gregory Munro’s house a few days before the murder,’ said Crane.

‘Yes, several of the photos on the laptop showed JordiLevi with Stephen Linley and Isaac Strong: photos of them having sex. Police searched Dr Strong’s house, and they found a small quantity of Ecstasy, marijuana and flunitrazepam, the drug used in all three murders. They also discovered several items of fetish gear: hoods and bags, the type of stuff used in erotic asphyxiation or breath control play – the semi-suffocation of yourself or your partner for sexual pleasure…’

Erika sat at the back of the room and her blood ran cold. Her mind began to race, thinking through the times she’d been to Isaac’s house. Could it be true?

‘Now, as always,’ continued Marsh, ‘a person is innocent until proven guilty, and there is added sensitivity in this case in that Dr Strong is one of our own, a fine forensic pathologist with an unblemished record. But the evidence against him has stacked up quite alarmingly, and so City Police had no choice but to arrest him for the murder of Stephen Linley. Isaac Strong is also now being looked at as a suspect for the murders of Gregory Munro and Jack Hart.’

‘So where does that leave us, the team?’ asked Erika.

Marsh paused. ‘As you all know, we need to maintain transparency. You have all done fine work on this case, and thank you to every one of you. DCI Foster, you have also been working alongside Dr Strong, and we must now look into his reports and see if he could have influenced the investigation. Dr Strong also phoned you from the crime scene, before he alerted the police…’