“I do not expect them to be here yet,” whispered Poirot to me. “Possibly they may not come until tomorrow night, but they know perfectly well that there are only two nights on which the radium will be there.”

Very cautiously we turned the key in the garden door. It opened noiselessly and we stepped into the garden.

And then, with complete unexpectedness, the blow fell. In a minute we were surrounded, gagged, and bound. At least ten men must have been waiting for us. Resistance was useless. Like two helpless bundles we were lifted up and carried along. To my intense astonishment, they took us towards the house and not away from it. With a key they opened the door into the laboratory and carried us into it. One of the men stooped down before a big safe. The door of it swung open. I felt an unpleasant sensation down my spine. Were they going to bundle us into it, and leave us there to asphyxiate slowly?