Outside on Budapester Strasse I fell in behind a group of schoolchildren as far as Ansbacher Strasse, where I got rid of the guidebook, slipped into the raincoat I was carrying, and turned up the brim of my hat. Minor alterations to your appearance are essential when following someone. There’s that, and staying in the open. It’s only when you start to cower in doorways that your man will get suspicious. But this fellow never even looked back as he crossed Wittenberg Platz, and went through the front door of Kaufhaus des Westens, the Ka-De-We, Berlin’s biggest department store.

I had thought that he had used the other carrier only to throw a tail off, somebody who might have been waiting at one of the exits on the look out for a man carrying a Gerson bag. But now I realized that we were also in for a switch.

The beer-restaurant on Ka-De-We’s third floor was full of lunchtime drinkers. They sat stolidly facing plates of sausage, and glasses of beer that were the height of table lamps. The youth carrying the money wandered among the tables as if looking for someone, and finally sat down opposite a man wearing a blue suit, sitting alone. He placed the carrier-bag with the money beside another just like it on the floor.

Finding an empty table I sat down just in sight of them, and picked up a menu which I affected to study. A waiter appeared. I told him I hadn’t made up my mind, and he went away again.

Now the man in the blue suit stood up, laid some coins on the table and, bending down, picked up the carrier bag with the money. Neither one of them said a word.

When the blue suit went out of the restaurant I followed him, obeying the cardinal rule of all cases involving ransom: you always go after the money.

With its massive arched portico and twin, minaret-like towers, there was a monolithic, almost Byzantine quality about the Metropol Theatre on Nollendorfplatz. Appearing on reliefs at the foot of the great buttresses were intertwined as many as twenty naked figures, and it seemed like the ideal kind of place to try your hand at a spot of virgin sacrifice. On the righthand side of the theatre was a big wooden gateway, and through it the car park, as big as a football pitch, which backed on to several tall tenements.

It was to one of these buildings that I followed Blue Suit and the money. I checked the names on the mailboxes in the downstairs hall, and was pleased to find a K. Hering residing at number nine. Then I called Bruno from a phone box at the U-Bahn station across the road.