Marlene Dietrich teams up with director and mentor Josef Von Sternberg for the last of their collaborations, in this romantic drama about a love-triangle involving a femme fatale. Set against the background of Spain's Carnaval, young army officer Antonio Galvin (Cesar Romero) is warned against getting involved with the seductive and sultry Concha Perez (Dietrich), whom he has just encountered. Although Don Pasqual (Lionel Atwill), the older officer warning him, tries his best to dissuade the younger man, telling him of her gold-digging ways, his pleas fall on deaf ears as Antonio soon becomes bewitched. When, days later, he stumbles upon the couple in the street, all of Pasqual's past jealousies and hurt resurface, forcing him to confront Antonio in a final, desperate bid for Concha's love.