Two beautiful young Australian sisters arrive in post-war London, where they encounter the men they'll know for the rest of their lives. Grace is fair, timid, conventional; Caro is dark, reserved and fiercely intelligent. Grace meets Christian Thrale, a successful and self-centered bureaucrat, whom she'll marry. Caro meets Ted Tice, a ginger-haired astronomist, awkward and brilliant, who falls in love with her. But Caro falls in love with Paul Ivory, a handsome playwright who treats her badly. None of these three marry each other: Paul marries a cold and beautiful aristocrat; Caro, a rich and distinguished American. That's not the end of the story, but it's all I'll tell you. The whole story is more complicated and more tragic, and it unfolds with calm inexorability.

(from http://www.npr.org/2013/09/15/221784628/love-story-electrifies-beneath-the-silhouette-of-venus).