Grau was at the head of the detective service at Ostend and invested with the task of ferreting out the numerous spies in the service of the Allies and dealing with them in a summary manner. He was a very stout man, and not very tall. His eyes were light blue and his grizzled mustache was a poor imitation of that affected by the Kaiser. When Grau looked up, on their entrance, Patsy decided that their appearance had startled him, but presently she realized that the odd expression was permanent.