"I think it's safe now. Stay close behind me and if I holler run like hell."

Wolfe's inarticulate growl, as I wheeled and headed for the office, warned me that there was barbed wire in that neighbourhood, so when he came in a few minutes later and got re-established in his chair I made no effort to explain my viewpoint any further. He drank beer and fiddled around with a pile of catalogues, while I checked over a couple of invoices from Hoehn's and did some miscellaneous chores. When a little later he asked me to please open the window a crack, I knew the tension was relaxing towards normal.

But if either or both of us had any idea that we were through with the Balkans for that day, it wasn't long before we had it jostled out of us. It was customary for Fritz to answer the doorbell from eleven on, when I was in the office with Wolfe. Around twelve-thirty he came in, advanced the usual three paces, stood formally, and announced a caller named Stahl who would not declare his business but stated that he was an agent of the Federal Bureau of Investigation.

I let out a low whistle and ejaculated cautiously "Aha!" Wolfe opened his eyes a trifle and nodded, and Fritz went for the caller.

We hadn't bumped into a G-man before in the course of business, and when he entered I did him the honour of swivelling clear around for a look. He was all right, medium-sized, with good shoulders and good eyes, a little skimpy in the jaw, and he needed a shoeshine. He told us his name again and shook hands with both of us, and took from his pocket a little leather case which he flipped open and exhibited to Wolfe with a reserved but friendly smile.