Although the bus made several stops on its slow interrupted journey to Sevenoaks, William saw nothing to make him think Faulkner would have got off before the final stop.

He checked his watch as a police pickup truck lumbered by. He wasn’t confident there would be any of Faulkner’s dabs on the Mercedes, but the chauffeur’s hat? Ross was waiting for him when the bus reached its final stop, and he clearly hadn’t wasted his time.

‘The first thing Faulkner would have seen when he got off the bus,’ Ross said, ‘was the railway station and the cab rank directly opposite, on the other side of the road. Danny’s already checking the station. So far I haven’t had any luck with the cabbies. None of them recognized the photograph of Ralph Neville, but they told me quite a few of the regulars prefer working afternoons.’

‘Then you’ll have to keep on asking, while I pay a visit to Mrs Rose Prescott.’

‘Who’s she?’

‘To be revealed later,’ said William, as he left Ross to return to the taxi rank, while he walked across to the terminus.

‘Rose,’ said the supervisor, once he’d checked the Chief Inspector’s warrant card. ‘She hasn’t done anything wrong, I hope.’

‘No, nothing. I’m just hoping she’ll remember a passenger who was on her bus yesterday afternoon.’

‘On that route they’re almost all regulars who she’d know personally.’ He began to turn the pages of a large folder. ‘She lives at number twenty-three Castle Drive.’ Checking his watch, he added, ‘She should be back from church by now.’

When William emerged from the terminus, he spotted Ross showing another taxi driver the blown-up photo of Neville, but the cabbie was shaking his head as William joined them.

‘It’s an outside chance,’ admitted William, ‘but don’t let the odds put you off.’

Ross mumbled something unintelligible, as William climbed into the back of the cab and gave the driver an address in Castle Drive. As the taxi moved off, he asked, ‘You didn’t recognize the man in the photograph my colleague showed you?’

‘No, guv. Yesterday afternoon I was watching Arsenal being stitched up by Chelsea.’

Now there’s a surprise, William wanted to say, but decided not to reveal his true colours in case the cabbie decided not to speak to him again. He sat back and began to think about the questions he needed to ask Mrs Prescott, who he felt he already knew.

When the taxi drew up outside No. 23, William said, ‘Can you hang about? I shouldn’t be too long.’

‘The meter will still be running,’ said the cabbie with a grin.

William opened the little wicket gate, walked down a short path and knocked on the front door. Moments later, a young woman answered it.

‘Is Mrs Prescott at home?’ he asked, after he had shown her his warrant card.

‘She’s just got back from church. I’ll go and fetch her.’

An older woman appeared a few moments later, dressed in her Sunday best. ‘Do come in, Chief Inspector,’ she said. ‘I was just about to make a cup of tea. Would you like one?’