Marianne has a life others dream of. A beautiful townhouse on the best street in the neighborhood. Three bright children who are her pride and joy. Sometimes her past still hurts: losing her mother, growing up in foster care. But her husband Simon is always there. A successful surgeon, he's the envy of every woman they've ever met. Flowers, gifts, trips to France - nothing is too good for his family. Then Simon says another woman's name. The way he lingers on it, Caroline, gives Marianne a shudder of suspicion, but she knows she can't entertain this flash of paranoia. In the old days, she'd have distracted herself at work, but Marianne left her glamorous career behind when she got married. She'd speak to a friend, but she's too busy with her children and besides, Simon doesn't approve of the few she has left. It's almost by accident that Marianne begins to learn more about Caroline. But once she starts, she can't stop. Because what she finds makes her wonder whether the question she should be asking is not 'should she be jealous', but... 'should she be scared'?