She had briefly forgotten her own troubles, diverted by this glimpse into Strike’s private world. So normal, so unremarkable! A party and he had gone along and got talking to the beautiful blonde. Women liked Strike—she had come to realize that over the months they had worked together. She had not understood the appeal when she had started working for him. He was so very different from Matthew.

“Does Ilsa like Elin?” asked Robin.

Strike was startled by this flash of perception.

“Er—yeah, I think so,” he lied.

Robin sipped her Coke.

“OK,” said Strike, restraining his impatience with difficulty, “your turn.”

“We’ve split up,” she said.

Interrogation technique told him to remain silent, and after a minute or so the decision was vindicated.

“He… told me something,” she said. “Last night.”

Strike waited.

“And we can’t go back from that. Not that.”

She was pale and composed but he could almost feel the anguish behind the words. Still he waited.

“He slept with someone else,” she said in a small, tight voice.

There was a pause. She picked up her crisp packet, found that she had finished the contents and dropped it on the table.

“Shit,” said Strike.

He was surprised: not that Matthew had slept with another woman, but that he had admitted it. His impression of the handsome young accountant was of a man who knew how to run his life to suit himself, to compartmentalize and categorize where necessary.

“And not just once,” said Robin, in that same tight voice. “He was doing it for months. With someone we both know. Sarah Shadlock. She’s an old friend of his from university.”

“Christ,” said Strike. “I’m sorry.”

He was sorry, genuinely sorry, for the pain she was in. Yet the revelation had caused certain other feelings—feelings he usually kept under tight rein, considering them both misguided and dangerous—to flex inside him, to test their strength against their restraining bonds.

Don’t be a stupid fucker, he told himself. That’s one thing that can never happen. It’d screw everything up royally.

“What made him tell you?” Strike asked.

She did not answer, but the question brought back the scene in awful clarity.

Their magnolia sitting room was far too tiny to accommodate a couple in such a state of fury. They had driven all the way home from Yorkshire in the Land Rover that Matthew had not wanted. Somewhere along the way, an incensed Matthew had asserted that it was a matter of time before Strike made a pass at Robin and what was more, he suspected that she would welcome the advance.

“He’s my friend, that’s all!” she had bellowed at Matthew from beside their cheap sofa, their weekend bags still in the hall. “For you to suggest I’m turned on by the fact he’s had his leg—”

“You’re so bloody naive!” he had bellowed. “He’s your friend until he tries to get you into bed, Robin—”

“Who are you judging him by? Are you biding your time before you jump on your coworkers?”