After spending five years in a closed convent school, Mona Vivienne goes to London and goes straight into the capital's highest society. The atmosphere of immorality that reigns there frightens the girl, but at the same time intoxicates her with an unusual freedom and sophistication. When the irresistible Alec Gordon appears in Mona’s house - a socialite, charming and carefree - the girl falls madly in love with him. And soon she faces a very difficult choice...