When the redoubtable Sir Horace Stanton-Lacy is ordered to South America on Diplomatic Business he parks his only daughter Sophy on his sister in Berkeley Square. But Sophy's cousins are in a sad tangle. The heartless and tyrannical Charles is betrothed to a pedantic bluestocking almost as tiresome as himself; Cecilia is besotted with a beautiful but quite feather-brained poet; and Hubert has fallen foul of a money-lender. It looks like the Grand Sophy has arrived just in time to save them all . . .