CHAPTER I. THE OBJECTIVE
CHAPTER II. THE WATCHERS
CHAPTER III. ACTION
CHAPTER IV. PERRY DAVISON,. MATHEMATICIAN
CHAPTER V. THE LAIR
CHAPTER VI. INTERLUDE
CHAPTER VII. "THE BEST-LAID. SCHEMES..."
CHAPTER VIII. THE MEETING IN. REGENT'S PARK
CHAPTER IX. END OF SONIA
CHAPTER X. THE HUB
CHAPTER XI. THE CLUES?
CHAPTER XII. AT THE "NEW. ORIENTAL"
CHAPTER XIII. "IF AT FIRST YOU. DON'T SUCCEED"
CHAPTER XIV. THE EYES
CHAPTER XV. THE CAVE IN THE. QUARRY
CHAPTER XVI. BILLY HARWOOD'S. PIECE
CHAPTER XVII. KING'S EVIDENCE
CHAPTER XVIII. MYSTERY FLAT
THE END
