Worse, in pursuit of the mischievous friend who tripped him, Babbs stumbled down steps--clutching at a rope to steady himself--and inadvertently rang a fire bell.

Babbs replies he is “only” in his 10th year and claims Charley Wykeham and Jack Chesney will corroborate the accidental ringing of the fire bell.

Charley receives word that his aunt, Donna Lucia d'Alvadorez, a rich widow from Brazil whom he has never met, is coming to visit him.

Donna Lucia’s solicitor, Hilary Babberley, informs her that her nephew Charley has fallen in love with the ward of the unsavory Mr. Spettigue.

Jack receives an unexpected visit from his father, Sir Francis Chesney, who reveals he has inherited debts that will affect their finances for a few years.

Jack suggests that Sir Francis marry Donna Lucia to clear the family debts.

Sir Francis meets “Donna Lucia” and cringes at the sight of “her.” Spettigue arrives, angry Kitty and Amy are lunching with the boys without his permission.

Meanwhile, the real Donna Lucia arrives, presenting to Babbs (in male attire) the letter of introduction from his uncle.

Mrs. Smythe is keenly interested in meeting “her.” Jack and Charley finally declare their love to their girls, discovering that they need Spettigue's consent to marry, in writing, so he cannot disclaim it.

Act III That evening at dinner with all the key players, Mrs. Smythe embarrasses “Donna Lucia” by exposing how little “she” knows about Brazil, coffee, and “her late husband” Don Pedro.