Erika turned and regarded a new addition to the whiteboard. A mugshot of Gary Wilmslow. In the photo he had a little more hair on his head, and stared into the camera with a glowering face and bags under his eyes.

‘So, the closest we’ve got to a suspect so far is the victim’s brother-in-law, Gary Wilmslow. There’s a motive: he hated Gregory and they’d had several run-ins. And his sister will inherit Gregory’s considerable estate. As a family, Gary, Penny and their mother seem as thick as thieves, if you excuse the pun. What have we got on Gary?’

The atmosphere in the incident room changed as Detective Chief Superintendent Marsh entered. Officers sat up straighter and looked more alert. Marsh perched on the long table of printers and indicated to Erika that she should keep going.

Crane stood up. ‘Okay, Gary Wilmslow, aged thirty-seven. Born in Shirley, South London. Currently works sixteen hours part-time as a bouncer at a nightclub in Peckham… Just enough hours for him to still claim benefits. He’s a charming individual, with a record as thick as a Miss Universe contestant,’ he said, dryly. He put his biro between his teeth and rooted around on his desk, locating a large file, which he opened. ‘Wilmslow was tried as a juvenile in 1993, for an attack on an old man at a bus stop on Neasden High Street. The old man was in a coma for three days but recovered to give evidence. Gary spent three years in Feltham Young Offender Institution for that one. Then in 1999 he was tried and found guilty of GBH and ABH, spent eighteen months inside. Did another two years from 2004 to 2006 for dealing drugs.’ Crane was flicking through pages in the thick file. ‘He got another eighteen months in 2006 for attacking a man in a snooker hall in Sydenham with a pool cue. He was charged with rape in 2008, but the charges were dropped due to insufficient evidence. He was then tried for manslaughter last year.’

‘That was whilst he was working as a bouncer?’ asked Erika.

‘Yeah, he works at the H20 nightclub in Peckham, or Haitch Twenty, as it’s known – and hated – by uniform division at the weekends. Gary Wilmslow’s barrister argued that he was acting in self-defence, and he was given a two-year sentence. He got out after one year and is currently on licence… What’s interesting is that his barrister was paid for by none other than Gregory Munro.’

Erika went back to the whiteboard and looked at Gary’s photo. The officers leaned back in chairs and there was a silence as they chewed it over.

‘Okay. So Gary Wilmslow’s a scumbag. He’s got a record as long as a crocodile’s arse, but did he do this?’ asked Erika, tapping the crime scene photos of Gregory Munro lying dead on his bed, arms bound to the headboard, his head misshapen through the plastic bag.

‘Gary Wilmslow’s also given us an alibi,’ said Crane.

‘He’s taking the piss with that alibi: they all stayed in watching TV!’ said Peterson, barely disguising his hatred.

‘Okay, but remember he’s out on licence and Penny is very protective. Please let’s not jump to conclusions,’ said Erika.

‘Boss! Look at his record, he’s more than capable. I say we bring him in.’

‘I hear you, Peterson, but this murder was planned very carefully and executed with real skill, leaving virtually no forensic evidence. Gary Wilmslow is an angry little thug.’ Erika took the file from Crane and flicked through. ‘All of these crimes were spur of the moment – violent, impetuous outbursts of anger.’

‘The motive of inheriting Gregory’s money is very strong,’ said Peterson. ‘Three London properties, a medical practice. Have we looked into life insurance? Gregory Munro would most probably have damn good coverage. And then there was the personal hatred towards him. The means of entry could have been staged,’ said Peterson.

‘Okay, I hear you,’ said Erika. ‘But we need more evidence if we are going to bring him in.’

DC Warren stood up.

‘Yes. What have you got?’ asked Erika.

‘Boss. We’ve had more stuff back from the lab. Four fibres have been lifted from the fence wire at the bottom of the garden; they are all from a piece of black clothing, a cotton Lycra mix. There’s been no luck with lifting any bodily fluids, though.’

‘What about behind the house? The railway line?’

‘Um, there’s a nature reserve,’ Warren stuttered, unnerved by Marsh’s silent presence watching from the back of the incident room. ‘It’s small, but it was created seven years ago by some local residents. It runs a quarter of a mile along the train tracks in the London-bound direction and then stops at Honor Oak Road before the train station… I’ve already requested CCTV from South West Trains on the night of the murder.’