On a foggy London night, Sir Gerald Courtney saves June, a prostitute, from being arrested on his doorstep by telling the police that she is his niece. In need of money, June agrees to use her charms to help Gerald rescue his son Russell from the clutches of Berthine Waller, a gold digger. After buying a lavish wardrobe on Gerald's expense account, June shows up at Russell's apartment building and, as a drunken Russell watches, pretends to be locked out of the apartment that she has just rented below his. While maintaining a ladylike facade, June lures him into her apartment and cajoles him into passing out on her bed. The next morning Russell wakes up in June's bed, having stood up Berthine the night before, and is mortified. After June assures him that he is still a gentleman, Russell begins to date her, then stops drinking and going out with Berthine and starts a promising career as an architect. Satisfied that Russell has reformed, Gerald and June declare their love for each other, and June, sure that he will understand, vows to tell Russell the truth. When June confesses that she is in love with his father, a heartbroken Russell denounces both her and Gerald and telephones Berthine. To prevent Russell from seeing Berthine upstairs, June pulls him into her apartment and pretends to be the callous "lady for hire" he believes her to be. Drunk, Russell passes out on June's bed again, unaware that Berthine has been murdered in his apartment by her jealous fortune-hunting partner, Nikolai Rabinoff. When Russell wakes up, he finds a farewell note from June, which admonishes him to forgive his father. Now the police's main murder suspect, Russell hides in his father's house but refuses to name June in his alibi. Eventually, June reveals that Russell spent the night in her place and is rejected by Gerald. Devastated by Gerald's lack of trust, June exits into the fog before Russell can explain that he was alone in June's apartment. A shamed Gerald then vows to follow June "wherever" she goes.