After Regina Lampert falls for the dashing Peter Joshua on a skiing holiday in the French Alps, she discovers upon her return to Paris that her husband has been murdered. Soon, she and Peter are giving chase to three of her late husband's World War II cronies, Tex, Scobie and Gideon, who are after a quarter of a million dollars the quartet stole while behind enemy lines.
In Victorian era London, the inhabitants of a family home with rented rooms upstairs fear the new lodger is Jack the Ripper.
Rich old Cyrus West's relatives are waiting for him to die so they can inherit. But he stipulates that his will be read 20 years after his death. On the appointed day his expectant heirs arrive at his brooding mansion. The will is read and it turns out that Annabelle West, the only heir with his name left, inherits, if she is deemed sane. If she isn't, the money and some diamonds go to someone else, whose name is in a sealed envelope. Before he can reveal the identity of her successor to Annabelle, Mr. Crosby, the lawyer, disappears. The first in a series of mysterious events, some of which point to Annabelle in fact being unstable.
Mystery writer Cornelia Van Gorder has rented a country house called "The Oaks", which not long ago was the scene of some murders committed by a strange and violent criminal known as "The Bat". Meanwhile, the house's owner, bank president John Fleming, has recently embezzled one million dollars in securities and has hidden the proceeds in the house, but is killed before he can retrieve it.