IV–––––––– MR. REEDER WENT BACK to Brockley that night in a discontented frame of mind. Give him the end of the thread, and he would follow it through all its complicated entanglements. He would sit patiently, untying knots, for days, for weeks, for months, even for years. But now he had not even the end of his thread. He had two isolated cases, distinct from one another, except that they were linked together by a similarity of method but, looking in all directions, he saw no daylight. The quietude of Brockley Road was very soothing to him. From near at hand came the gentle whirr of traffic passing up and down the Lewisham High Road, the rumble of lorries and the shrill voices of boys calling the final editions of the evening newspapers. In the serenity of his home Mr. Reeder recuperate