It is a dark and stormy night at Sterne, the beloved family home of Charlotte Torrington Swift and her children, Clovis, Emerald, and Imogen, better known as Smudge. After Charlotte’s first husband, Horace, died, she quickly remarried Edward Swift, a lawyer with only one arm, whose relationship with her children has been less than affectionate. Edward is departing to Manchester on a most important mission: he must attempt to borrow enough money to safe Sterne or it will be lost.
And on this 1912 evening, preparations are underway for Emerald’s twentieth birthday dinner which is to be attended by her best friend, Patience, along with Patience’s mother. The housekeeper, Florence, along with her daughter, Myrtle, is busily preparing an elaborate dinner and birthday cake, and unbeknownst to everyone else, nine-year-old Smudge is plotting a “Great Undertaking.”