Trying to get away from an engagement he had got himself into more or less against his will, Stephen Knight travels to Algiers to visit his old friend Nevill. On the Journey there he meets the charming and beautiful Victoria. She is on her way to Algiers to search for her sister, who had disappeared years ago after marrying an Arab nobleman. With the support of his friend, Stephen Knight decides to help the girl - but when she also disappears, the adventure begins...

The passengers in the sleeping car of the Rome Express were just woken and informed that they will reach Paris soon, and a general bustle fills the train. Only one passenger cannot be awoken by the porter, no matter how loudly he knocks on the compartment door. At last, when the door is forced open, the occupant of the compartment is found dead - stabbed to the heart! The murderer must be found among the passengers...