"I am not by nature a spy, Professor Kennedy, but-well, sometimes one is forced into something like that." Maude Euston, who had sought out Craig in his laboratory, was a striking girl, not merely because she was pretty or because her gown was modish. Perhaps it was her sincerity and artlessness that made her attractive. She was the daughter of Barry Euston, president of the Continental Express Company, and one could readily see why, aside from the position her father held, she should be among the most-sought-after young women in the city.