She was touchingly averse to charging minor luxuries to petty cash. Robin made no objection in front of their guest, but thanked Strike, and turned again to her work, which involved a small clockwise swivel of her desk chair, away from the two men.

The flare of a match turned Strike’s attention from his own double espresso to his guest.

‘This is a non-smoking office, Spanner.’

‘What? You smoke like a fucking chimney.’

‘Not in here I don’t. Follow me.’

Strike led Spanner into his own office and closed the door firmly behind him.

‘She’s engaged,’ he said, taking his usual seat.

‘Wasting my powder, am I? Ah well. Put in a word for me if the engagement goes down the pan; she’s just my type.’

‘I don’t think you’re hers.’

Spanner grinned knowingly.

‘Already queuing, are you?’

‘No,’ said Strike. ‘I just know her fiancé’s a rugby-playing accountant. Clean-cut, square-jawed Yorkshireman.’

He had formed a surprisingly clear mental image of Matthew, though he had never seen a photograph.

‘You never know; she might fancy rebounding on to something a bit edgier,’ said Spanner, swinging Lula Landry’s laptop on to the desk and sitting down opposite Strike. He was wearing a slightly tatty sweatshirt and Jesus sandals on bare feet; it was the warmest day of the year so far. ‘I’ve had a good look at this piece of crap. How much technical detail do you want?’

‘None; but I need to know that you could explain it clearly in court.’

Spanner looked, for the first time, truly intrigued.

‘You serious?’

‘Very. Would you be able to prove to a defending counsel that you know your stuff?’

‘’Course I could.’

‘Then just give me the important bits.’

Spanner hesitated for a moment, trying to read Strike’s expression. Finally he began:

‘Password’s Agyeman, and it was reset five days before she died.’

‘Spell it?’

Spanner did so, adding, to Strike’s surprise: ‘It’s a surname. Ghanaian. She bookmarked the homepage of SOAS – School of Oriental and African Studies – and it was on there. Look here.’

As he spoke, Spanner’s nimble fingers were clacking keyboard keys; he had brought up the home page he described, bordered with bright green, with sections on the school, news, staff, students, library and so on.

‘When she died, though, it looked like this.’

And with another outburst of clicking, he retrieved an almost identical page, featuring, as the rapidly darting cursor soon revealed, a link to the obituary of one Professor J. P. Agyeman, Emeritus Professor of African Politics.

‘She saved this version of the page,’ said Spanner. ‘And her internet history shows she’d browsed Amazon for his books in the month before she died. She was looking at a lot of books on African history and politics round then.’

‘Any evidence she applied to SOAS?’

‘Not on here.’

‘Anything else of interest?’