This is actually a book with 7 short stories in it all featuring The Continental Op who is an agent with Continental Detective Agency. Hard boiled American detective fiction they are all set in a time in history when cars were referred to as automobiles and having one was unusual. Telephones - we'd call them land-lines now - were also rare and telegrams were sent regularly and life was altogether totally different.
The stories are very good indeed with great characters, storylines and action and a whole lexicography of slang detective type language, which I'm sure doesn't exist today, either.
Recommended.