Lady Jane Brooke, left by her parents to molder in a North Country mansion, sets out for London in an ancient carriage. When it collapses, she and her lady-companion continue the journey by mail coach. Lost in a fog, they and the other passengers take refuge at the home of Lord Wintringham, where they are anything but welcome. The starchy lord takes Jane for a governess. When they meet again in London, Jane continues the masquerade and gradually finds out that Lord Wintringham is not half as frosty as he's been painted.