The car passed through a couple of military checkpoints before we parked and entered a temple-like portico. Behind this were some bronze doors and on the other side a capacious hallway with a large American flag, several American soldiers, and two curving staircases covered with sheet aluminum. In front of the paternoster elevator I was invited to step aboard and to disembark on the ninth floor. A little nervously—for I had never before ridden one of these intimidating elevators—I complied.

The ninth floor was very different from those below. There were no windows. It was lit from skylights instead of banded glazing, which probably afforded the security-minded inhabitants yet more privacy. The ceiling was also much lower, which made me wonder if one of the qualifications to be an American spy in Europe might be a lack of height.

Certainly, the man to whom I was now introduced was not tall, although he was hardly short, either. He wasn’t anything you could have described, being unremarkable in almost every way. He was, I suppose, like an American professor, albeit one who spoke fluent German. He wore a blazer, gray flannel trousers, a button-down blue shirt, and some sort of club or academic tie—maroon with little shields. The introduction was not, however, illuminating in that he appeared to have no name, just a title. He was “the Chief,” and that was all I ever knew about him. I did, however, recognize the two men who were also waiting for me in that windowless meeting room. Special Agents Scheuer and Frei—were those their real names? I still had no idea—waited until the Chief had acknowledged their presence before nodding at me with silent courtesy.

“Have you been here before?” he asked. “I mean, when this building was owned by I. G. Farben.”

“No, sir.” I shrugged. “As a matter of fact, I’m surprised to find it’s still here. Apparently undamaged. A building this size, of such importance to the Nazi war effort—I’d always assumed it was bombed to rubble, like almost everything else in this part of Germany.”

“There are two schools of opinion on that, Gunther. Sit down, sit down. One school has it that the Americans forbidden to bomb it because of the building’s proximity to the Allied POW camp at Grüneburgpark. The other school would have you believe that Eisenhower had this building marked out as his future European headquarters. Apparently, the building reminded him of the Pentagon, in Washington. And I suppose, if I’m honest, it does look a little similar. So maybe that’s the real explanation after all.”

I drew a chair out from a long, dark wood table and sat down and waited for the Chief to get to the point of my being there. But it seemed he hadn’t yet finished with Eisenhower.