Mrs. Poole says she's taking a Balkans cruise, which would imply Greece and the eastern Mediterranean, but it's mentioned that they are visiting the Norwegian fjords and she disembarks in Hamburg, Germany, a port on Elbe River and North Sea. She must have meant Baltic, not Balkans.

A rare role for Una O'Connor where she's not playing a servant of some kind.

Mrs. Poole books travel on the fictional ship "Nebula" of the Blue Star Line, which was a real British passenger & cargo shipping company that operated from 1911-1998.