A virtuous woman's purity is threatened by a callow seducer. The eponymous heroine is a revered "doctor" in the neighborhood of alleys where she lives and dispenses free treatment to all who ask. She is called to nurse a wealthy crank, and his playboy youngest brother falls in love with her. She demands marriage when offered the status of mistress - and much chicanery and humor accompany the pathos of her struggle to gain respect via a common law document.