“Your investigative method, perhaps? You could tell me something about that.”

“My method was a bit like what Field Marshal von Moltke said about a battle plan. It never survives contact with the enemy. People are different, Richard. It stands to reason that homicides are different, too. Perhaps if you were to tell me about a case you’re working on now. Better still, if you brought me the file, I could take a look at it and offer my thoughts. The chief mentioned one case that needed warming up. The murder of that cop. August Krichbaum, wasn’t it? Perhaps I could suggest something there.”

“That’s no longer a cold case,” said Bömer. “Looks like there may be a lead, after all.”

I bit my lip. “Oh? What’s that?”

“Krichbaum got himself murdered in front of the Kaiser Hotel, right? Pathologist reckoned someone clouted him in the gut.”

“Must have been quite a punch.”

“I guess if you’re not ready for it, it might be. Anyway, the hotel doorman got a look at the main suspect. Not much of a look, but he’s an ex-cop. Anyway, he’s looked at the photograph of every crook in Berlin, and no luck. Since then he’s been racking his brains and now reckons that the fellow who hit Krichbaum might have been another cop.”

“A cop? You’re joking.”

“Not at all. They’ve got him looking over the personnel files of the entire Berlin police force, past and present. As soon as he thumbs the right mug, they’ll have the guy, for sure.”

“Well, that’s a relief.”

I lit a cigarette and rubbed the back of my neck uncomfortably, as if I could already feel the blade of the falling ax. It’s said that all you ever feel is a sharp bite, like the angry nip of the electric clippers in a gentlemen’s hairdressers. It took me a moment or two to remind myself that the hotel doorman’s description of the suspect had been of a man with a mustache. And it took me a while longer to remember that in the original photograph on my own police personnel file I had been wearing a mustache. Did that make it more or less likely that he could identify me? I wasn’t sure. I took a deep breath and felt my head swim a little.

“But I brought the file on something else I’ve been working on,” said Bömer, unbuckling his saddle-leather briefcase.

“Good,” I said, without enthusiasm. “Oh, good.”

He handed me a buff-colored file.

“A few days ago, there was a body found floating in the Mühlendamm Lock.”

“A Landwehr Top,” I said.

“I beg your pardon?”

“Nothing. So why didn’t the Mühlendamm Murder Commission deal with it?”

“Because there was some mystery about the man’s identity and about the cause of death. The man drowned. But the body was full of seawater, see? So he couldn’t possibly have drowned in the River Spree.” He handed me some photographs. “Plus, as you can see, an attempt had been made to weigh the body down. The rope around the ankles probably slipped the weight.”