A portrait of a complex, ambitious at times mercenary and ruthless, at others alluring woman told from the perspective of the three men whose lives she impacted most.
In a way it's strange since the lead character of Ada Dallas doesn't have a voice of her own in the story merely those men's impressions of her actions but she is still a vivid character with unknowable qualities. However as described Ada may have retained that air of mystery even if her viewpoint was given since you get a sense that even she did not fully understand herself.
The book was adapted into a (much different) movie in the sixties starring Susan Hayward, an artist rendering of whom adorns the cover. Though she is described as somewhat physically different a few times in the book having that picture and being familiar with the actress and her tough no-nonsense screen persona (this character is right in her wheelhouse) envisioning her throughout the novel helped in making Ada a flesh and blood creation.
It's a dense read but an interesting one about a group of very flawed people.