Two sisters: beautiful, sophisticated Louise and attractive, witty and intelligent Sarah who has always felt left behind. Then Louise marries the wealthy but unappealing novelist Stephen Halifax, and Sarah, recently graduated from Oxford, is thrown back into family affairs. As Louise enters a high-profile world of glamour, parties and gossip columns, Sarah, drifting in London with her degree and new-found freedom, is only allowed glimpses into this new alien life. However, as the cracks begin to show in Louise's marriage and rumours of infidelity spread, Sarah discovers that, beneath her cool exterior, her sister is not quite the person she thought she was....