He had anticipated trouble, but pistol-shots in broad daylight, even in Grave Street, had been outside his calculations. He had recognised the peculiar report of an automatic pistol. His adversaries, whoever they might be, were obviously very much in earnest. Pistol-shooting at detectives is not a commonplace pastime even with the most reckless of criminals. Foyle decided on another and early visit to Grave Street, and prom
ised himself grimly that the target should be some one else, if it came to shooting again. He was in danger of losing his temper.
Not until he had got in the train did he open the note that was still between his fingers. He frowned as he read it.
"Curse it! This comes of acting on impulse. Why couldn't I have waited! I had the whole thing in my hands."
The note said simply—
"I am alive. I must see you. Follow the man who gives you this note.—R. G."
Heldon Foyle had seen much of Robert Grell's writing during his search of the house in Grosvenor Gardens, and had no doubt that the note was his. His peace of mind was not increased by the reflection that had he waited and continued to shadow Fairfield he might have discovered the whereabouts of the missing diplomat. Now he had merely given notice as plainly as though he had shouted from the housetops that Fairfield was under observation. He had committed a blunder, and he did not forgive blunders easily, especially in himself.
Even a bath and a change into his normal clothing did not restore his equanimity. In his office he found Green, with a strange excitement in his usually stolid face.
"Hello, Mr. Green. What's wrong?" he demanded.
The veteran chief detective-inspector pulled at his moustache.