Sea-going private detectives George Porter Dillman and Genevieve Masefield temporarily forsake the Cunard Line to work aboard the MINNESOTA, on a cruise to the Far East. Their hopes of an uneventful journey are dashed with the murder of a fiery Catholic missionary, which proves to be only the first in a series of crimes that will stretch them to the limit. Dillman and Genevieve have to use all their skills to combat danger and prevent an otherwise idyllic (and romantic) trip from becoming a terrifying nightmare.