"e;The Mysterious Key and What It Opened"e; is a 1867 novel written by Louisa May Alcott. The story revolves around Lillian Trevlyn who, when only a baby, loses her father and almost loses her mother on the same day. As the years pass Lillian becomes a respectable young woman, but without ever having learnt the truth about that fateful day. That is, until Paul, an orphaned boy, enters the ...