The best Dorothy Sebastian’s mystery movies

One dark foggy London night, someone tries to strangle Lord Montague, but he escapes. Only to discover the four other men who did get killed were old regimental comrades in Gallipoli. When Scotland Yard gets Monty to gather the other nine surviving officers at his home, one of them is murdered, and no one else has entered the house. Now, they must determine who the murderer is.

A mentally unstable man, who has been kept in isolation for years, escapes and causes trouble for his identical twin brother.

A diamond is stolen at a houseboat party given by the district attorney. He gives the thief a chance to return it by putting an empty box on a table and turning out the lights. When the lights are turned back on the box is gone, and the district attorney has a knife in his back and is quite dead. The police and the coroner arrive. There are several attempts made on the life of the coroner. Ruth Whitman is found hiding in a grandfather-clock, holding the gem box. She claims the box was pushed into her hands and she was pushed into the clock. The district attorney's butler/valet tells the coroner he saw who killed his employer and a few minutes later he is also murdered. The mystery deepens.