Wada was tempted to call Dobachi before she met Erla, to see if there was any news of the police investigation into Kodaka’s killing. But she reminded herself, as she marched along the waterfront promenade with the drizzle thickening around her, that she wasn’t supposed to be in Iceland and she wasn’t supposed to be pursuing the mystery of her boss’s death at all. She was on her own. And it had to stay that way.

Reykjavík Roasters was crowded with students tapping at laptops and iPhones and gaggles of young mothers with toddlers in pushchairs. Wada took her coffee to the bench by the window and gazed out as she sipped it, eyeing the passers-by and trying to guess which one might be Erla. Numerous candidates walked past in the form of willowy young blonde-haired Icelandic women, but none of those who entered the coffee shop approached her, though as the sole Asian on the premises she was easy to spot.

Then her phone rang.

‘Hello?’

‘This is Erla. You can see a Euromarket across the street, yes?’

There was a convenience store on the other side of the road. From where she was Wada couldn’t be sure of the name, but she reckoned that was the place Erla meant. ‘I see it.’

‘I’m just coming out.’

As Wada watched, a young woman stepped into view from inside the shop. She was, as Wada had expected, tall, young, slim and blonde. She was wearing jeans and a yellow anorak. She looked in Wada’s direction and started walking.

‘Follow me.’

Erla ended the call there and put her phone in her pocket. Wada abandoned her coffee, shrugged on her coat and set off after her.

Erla kept up a steady pace and didn’t look back. Wada closed the gap between them, then slowed slightly. She thought it best not to catch up.

They crossed a side street and arrived outside a large, modern three-storey building decorated in garish shades of red, blue and yellow. It was the Stúdentagarđar, according to a large sign on the wall. Wada’s guess was that it was a student hall of residence, which explained why there’d been so many students in Reykjavík Roasters.

Erla entered a central courtyard and climbed the stairs to the second floor, then followed the open walkway along to the door of flat 240. She still didn’t look back, though she must have been aware Wada was following her. She let herself in, but left the door ajar.

Wada pushed the door open just far enough to slip inside, glancing along the walkway as she did so. There was no one in sight.