What Every Woman Knows follows the clever Wylie family of Scotland, whose lives change when they catch a young man, John Shand, attempting to burgle their home. Rather than turn him in, they strike a bargain: they'll finance his education and help him rise in the world, on the condition that he marries their daughter Maggie. John agrees, viewing it as a practical arrangement, and the family sets him on a path to success in politics and public life. Years later, as John becomes a celebrated and ambitious man, he takes credit for his own achievements and grows distant from Maggie, falling under the spell of a glamorous countess. Maggie, however, possesses a quiet wisdom and understanding that proves far more valuable than anyone realizes. The play explores the invisible influence women wield in shaping men's destinies, the nature of true partnership, and the power of genuine love over superficial attraction. Through witty dialogue and tender moments, the story reveals that behind every successful man stands a woman whose contributions often go unrecognized—and that real strength lies not in ambition, but in knowing one's true worth.