Spy gadgets

My father collected the murderous kind of spy gadget. No clever codes or microdots, just hidden knives and poison rings and beautiful things that were guns. All the most thrilling toys a boy could be forbidden. By the time he left them to me, I had outgrown my fascination. All I wanted was to read his old diaries, and get to know the man inside. When I opened the first volume, it gave a click. There was an empty space where the explosive charge should be.