At 11.30am Grant Grubb appeared at Parkside station. He was wearing his work clothes, which included a T-shirt with ‘Grant does Windows’ written on it. Not very catchy, Barrett thought to himself as he showed the nervous looking man into the same interview room that the Boltons had been in earlier that morning.

‘Take a seat, Mr Grubb.’ Barrett leant against the wall with his hands behind his back, knowing the position of his body would assert authority.

‘Do I need a brief?’ Grant rubbed his sweaty neck with one of his large, rough hands.

‘That is for you to decide. You are not under arrest … currently.’ Barrett watched as Grant swallowed hard, his Adam’s apple bobbing up and down like a golf ball in his throat.

‘I’m not really sure why I’m ’ere.’ His thick Cambridgeshire accent grated on Barrett and DS Singh – who was also participating in the interview.

‘We want to talk to you about your relationship with Toni Jones.’ Barrett spoke calmly, never taking his eyes off Grant.

‘Didn’t really know her.’ Grant folded his arms across his broad chest.

‘That’s not what we’ve heard, Mr Grubb.’

‘Oh?’ Grant shrugged and looked down at his filthy nails.

‘We understand that you had an affair with Mrs Jones, around the time her first marriage ended.’

Grant sat, button-lipped.

‘I understand that this is a delicate situation, Mr Grubb, but if you don’t want to cooperate, perhaps we should speak to your wife?’

Grant’s eyes bulged and he shook his head.

‘No, not my missus. She don’t know about it. You can’t.’ Singh moved his chair back a few inches: the man opposite him stank of stale body odour, and he wondered when that T-shirt had last been washed.

‘Mr Grubb.’ Barrett pulled out a chair and sat down, instantly regretting his move due to the stench that was coming from the man opposite. Singh could see from Barrett’s face that he too wished the room had a window. ‘I am not interested in harming your marriage, I simply want to know the details of your alleged affair with Toni Jones. It is better for you in the long run if you tell us what you know.’

Grant sat and looked from Singh to Barrett while he contemplated his position.

‘What do you want to know exactly?’

‘When the affair started, how long it lasted, why it ended.’ Barrett reeled off the list, frustrated by the man’s stupidity. ‘How about you start with where you first met?’ Barrett’s patience was wearing thin.