On the 25th of October, 1892, the following note appeared in the latest edition of the “Temps”:
“A frightful crime has been committed at the Glandier, on the border of the forest of Sainte-Genevieve, above Epinay-sur-Orge, at the house of Professor Stangerson. On that night, while the master was working in his laboratory, an attempt was made to assassinate Mademoiselle Stangerson, who was sleeping in a chamber adjoining this laboratory. ...”
Aspiring detective, Joseph Rouletabille, along with his friend, Sainclair, set off to investigate the crime. He is told that a short Time after Mathilde Stangerson, daughter of Professor Joseph Stangerson, locked the single bolted door from inside the small yellow room adjacent to the laboratory in the pavilion where she worked with her father, she cried “Murder!” and two shots were fired. By the time her door was broken down, she is found unconscious on the floor. There is only one inaccessible barred and locked window in the room. Two witnesses, who were outside the door when it happened, corroborated the sequence of events.