A respectable English doctor, Phabos, collects precious stones. At one of the balls he meets a girl wearing a necklace with bronze “pearls”—pearls stolen from the doctor three years earlier. The doctor is intrigued by the boldness with which the thieves show him the stolen jewels. Phabos suspects the girl’s father, assuming he is the leader of an elusive gang of thieves who steal from wealthy, respectable people in several countries. As he begins his investigation, the doctor suspects the gang must have an unusual hideout, since police in several countries can’t find them. Dr. Phabos follows the trail of the young girl and her father.