‘Early bird gets the worm,’ said Lesley. ‘You know that picture you sent me, the one of Brandon Coopertown? I think he boarded a number 24 at Leicester Square less than ten minutes after the murder.’

‘Have you told Seawoll?’

‘’Course I have,’ said Lesley. ‘I love you dearly, but I ain’t going to fuck up my career for you.’

‘What did you tell him?’

‘That I had a lead on WITNESS A, one of several hundred generated in the last two days, I might add.’

‘What did he say?

‘He told me to check it out,’ said Lesley.

‘According to Mrs Coopertown he should be back today.’

‘Even better.’

‘Can you pick me up?’ I asked.

‘’Course,’ said Lesley. ‘What about Voldemort?’

‘He’s got my number,’ I said.

I had time for a shower and a coffee before meeting Lesley outside. She arrived in a ten-year-old Honda Accord that looked like it had been used in one too many drug raids. She gave me a sour look as Toby scrambled onto the back seat.

‘This is just a borrow, you know,’ she said.

‘I wasn’t about to leave him in my room,’ I said as Toby snuffled God knows what from the gaps between the seats. ‘Are you sure it was Coopertown?’

Lesley showed me a couple of hard copies. The bus security camera was angled to get a good shot of anyone coming up the stairs and there was no mistaking the face – it was him.

‘Is that bruising?’ I asked. There appeared to be blotches on Coopertown’s cheeks and neck. Lesley said she didn’t know but it had been a cold night, so it could have been from drink.

Because it was Saturday the traffic was merely horrendous, and we made Hampstead in just under half an hour. Unfortunately as we pulled into Downshire Hill I spotted the familiar silver shape of the Jaguar nestled among the Range Rovers and BMWs. Toby started yapping.

‘Doesn’t he ever sleep?’ asked Lesley.

‘I reckon he was on obbo all night,’ I said.

‘He ain’t my governor,’ said Lesley, ‘so I’m going to go do the job. Coming?’

We left Toby in the car and headed for the house. Inspector Nightingale got out of his Jag and intercepted us just short of the front gate. I noticed he was wearing the same suit he had been in the night before.

‘Peter,’ he said, and inclined his head to Lesley. ‘Constable May. I take it this means your search was successful?’

Even the Queen of Perky wasn’t going to defy a senior officer to his face, so she told him about the CCTV footage from the bus and how we were ninety per cent certain, what with the evidence from our ghost-hunting dog, that Brandon Coopertown, at the very least, was WITNESS A if not actually the killer.

‘Have you checked his flight details with Immigration yet?’ asked Nightingale.